nfsd4: Fix filp leak
[linux-2.6.git] / fs / ocfs2 / stack_o2cb.c
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * stack_o2cb.c
5  *
6  * Code which interfaces ocfs2 with the o2cb stack.
7  *
8  * Copyright (C) 2007 Oracle.  All rights reserved.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public
12  * License as published by the Free Software Foundation, version 2.
13  *
14  * This program 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 the GNU
17  * General Public License for more details.
18  */
19
20 #include <linux/kernel.h>
21 #include <linux/crc32.h>
22 #include <linux/slab.h>
23 #include <linux/module.h>
24
25 /* Needed for AOP_TRUNCATED_PAGE in mlog_errno() */
26 #include <linux/fs.h>
27
28 #include "cluster/masklog.h"
29 #include "cluster/nodemanager.h"
30 #include "cluster/heartbeat.h"
31
32 #include "stackglue.h"
33
34 struct o2dlm_private {
35         struct dlm_eviction_cb op_eviction_cb;
36 };
37
38 static struct ocfs2_stack_plugin o2cb_stack;
39
40 /* These should be identical */
41 #if (DLM_LOCK_IV != LKM_IVMODE)
42 # error Lock modes do not match
43 #endif
44 #if (DLM_LOCK_NL != LKM_NLMODE)
45 # error Lock modes do not match
46 #endif
47 #if (DLM_LOCK_CR != LKM_CRMODE)
48 # error Lock modes do not match
49 #endif
50 #if (DLM_LOCK_CW != LKM_CWMODE)
51 # error Lock modes do not match
52 #endif
53 #if (DLM_LOCK_PR != LKM_PRMODE)
54 # error Lock modes do not match
55 #endif
56 #if (DLM_LOCK_PW != LKM_PWMODE)
57 # error Lock modes do not match
58 #endif
59 #if (DLM_LOCK_EX != LKM_EXMODE)
60 # error Lock modes do not match
61 #endif
62 static inline int mode_to_o2dlm(int mode)
63 {
64         BUG_ON(mode > LKM_MAXMODE);
65
66         return mode;
67 }
68
69 #define map_flag(_generic, _o2dlm)              \
70         if (flags & (_generic)) {               \
71                 flags &= ~(_generic);           \
72                 o2dlm_flags |= (_o2dlm);        \
73         }
74 static int flags_to_o2dlm(u32 flags)
75 {
76         int o2dlm_flags = 0;
77
78         map_flag(DLM_LKF_NOQUEUE, LKM_NOQUEUE);
79         map_flag(DLM_LKF_CANCEL, LKM_CANCEL);
80         map_flag(DLM_LKF_CONVERT, LKM_CONVERT);
81         map_flag(DLM_LKF_VALBLK, LKM_VALBLK);
82         map_flag(DLM_LKF_IVVALBLK, LKM_INVVALBLK);
83         map_flag(DLM_LKF_ORPHAN, LKM_ORPHAN);
84         map_flag(DLM_LKF_FORCEUNLOCK, LKM_FORCE);
85         map_flag(DLM_LKF_TIMEOUT, LKM_TIMEOUT);
86         map_flag(DLM_LKF_LOCAL, LKM_LOCAL);
87
88         /* map_flag() should have cleared every flag passed in */
89         BUG_ON(flags != 0);
90
91         return o2dlm_flags;
92 }
93 #undef map_flag
94
95 /*
96  * Map an o2dlm status to standard errno values.
97  *
98  * o2dlm only uses a handful of these, and returns even fewer to the
99  * caller. Still, we try to assign sane values to each error.
100  *
101  * The following value pairs have special meanings to dlmglue, thus
102  * the right hand side needs to stay unique - never duplicate the
103  * mapping elsewhere in the table!
104  *
105  * DLM_NORMAL:          0
106  * DLM_NOTQUEUED:       -EAGAIN
107  * DLM_CANCELGRANT:     -EBUSY
108  * DLM_CANCEL:          -DLM_ECANCEL
109  */
110 /* Keep in sync with dlmapi.h */
111 static int status_map[] = {
112         [DLM_NORMAL]                    = 0,            /* Success */
113         [DLM_GRANTED]                   = -EINVAL,
114         [DLM_DENIED]                    = -EACCES,
115         [DLM_DENIED_NOLOCKS]            = -EACCES,
116         [DLM_WORKING]                   = -EACCES,
117         [DLM_BLOCKED]                   = -EINVAL,
118         [DLM_BLOCKED_ORPHAN]            = -EINVAL,
119         [DLM_DENIED_GRACE_PERIOD]       = -EACCES,
120         [DLM_SYSERR]                    = -ENOMEM,      /* It is what it is */
121         [DLM_NOSUPPORT]                 = -EPROTO,
122         [DLM_CANCELGRANT]               = -EBUSY,       /* Cancel after grant */
123         [DLM_IVLOCKID]                  = -EINVAL,
124         [DLM_SYNC]                      = -EINVAL,
125         [DLM_BADTYPE]                   = -EINVAL,
126         [DLM_BADRESOURCE]               = -EINVAL,
127         [DLM_MAXHANDLES]                = -ENOMEM,
128         [DLM_NOCLINFO]                  = -EINVAL,
129         [DLM_NOLOCKMGR]                 = -EINVAL,
130         [DLM_NOPURGED]                  = -EINVAL,
131         [DLM_BADARGS]                   = -EINVAL,
132         [DLM_VOID]                      = -EINVAL,
133         [DLM_NOTQUEUED]                 = -EAGAIN,      /* Trylock failed */
134         [DLM_IVBUFLEN]                  = -EINVAL,
135         [DLM_CVTUNGRANT]                = -EPERM,
136         [DLM_BADPARAM]                  = -EINVAL,
137         [DLM_VALNOTVALID]               = -EINVAL,
138         [DLM_REJECTED]                  = -EPERM,
139         [DLM_ABORT]                     = -EINVAL,
140         [DLM_CANCEL]                    = -DLM_ECANCEL, /* Successful cancel */
141         [DLM_IVRESHANDLE]               = -EINVAL,
142         [DLM_DEADLOCK]                  = -EDEADLK,
143         [DLM_DENIED_NOASTS]             = -EINVAL,
144         [DLM_FORWARD]                   = -EINVAL,
145         [DLM_TIMEOUT]                   = -ETIMEDOUT,
146         [DLM_IVGROUPID]                 = -EINVAL,
147         [DLM_VERS_CONFLICT]             = -EOPNOTSUPP,
148         [DLM_BAD_DEVICE_PATH]           = -ENOENT,
149         [DLM_NO_DEVICE_PERMISSION]      = -EPERM,
150         [DLM_NO_CONTROL_DEVICE]         = -ENOENT,
151         [DLM_RECOVERING]                = -ENOTCONN,
152         [DLM_MIGRATING]                 = -ERESTART,
153         [DLM_MAXSTATS]                  = -EINVAL,
154 };
155
156 static int dlm_status_to_errno(enum dlm_status status)
157 {
158         BUG_ON(status < 0 || status >= ARRAY_SIZE(status_map));
159
160         return status_map[status];
161 }
162
163 static void o2dlm_lock_ast_wrapper(void *astarg)
164 {
165         struct ocfs2_dlm_lksb *lksb = astarg;
166
167         lksb->lksb_conn->cc_proto->lp_lock_ast(lksb);
168 }
169
170 static void o2dlm_blocking_ast_wrapper(void *astarg, int level)
171 {
172         struct ocfs2_dlm_lksb *lksb = astarg;
173
174         lksb->lksb_conn->cc_proto->lp_blocking_ast(lksb, level);
175 }
176
177 static void o2dlm_unlock_ast_wrapper(void *astarg, enum dlm_status status)
178 {
179         struct ocfs2_dlm_lksb *lksb = astarg;
180         int error = dlm_status_to_errno(status);
181
182         /*
183          * In o2dlm, you can get both the lock_ast() for the lock being
184          * granted and the unlock_ast() for the CANCEL failing.  A
185          * successful cancel sends DLM_NORMAL here.  If the
186          * lock grant happened before the cancel arrived, you get
187          * DLM_CANCELGRANT.
188          *
189          * There's no need for the double-ast.  If we see DLM_CANCELGRANT,
190          * we just ignore it.  We expect the lock_ast() to handle the
191          * granted lock.
192          */
193         if (status == DLM_CANCELGRANT)
194                 return;
195
196         lksb->lksb_conn->cc_proto->lp_unlock_ast(lksb, error);
197 }
198
199 static int o2cb_dlm_lock(struct ocfs2_cluster_connection *conn,
200                          int mode,
201                          struct ocfs2_dlm_lksb *lksb,
202                          u32 flags,
203                          void *name,
204                          unsigned int namelen)
205 {
206         enum dlm_status status;
207         int o2dlm_mode = mode_to_o2dlm(mode);
208         int o2dlm_flags = flags_to_o2dlm(flags);
209         int ret;
210
211         status = dlmlock(conn->cc_lockspace, o2dlm_mode, &lksb->lksb_o2dlm,
212                          o2dlm_flags, name, namelen,
213                          o2dlm_lock_ast_wrapper, lksb,
214                          o2dlm_blocking_ast_wrapper);
215         ret = dlm_status_to_errno(status);
216         return ret;
217 }
218
219 static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn,
220                            struct ocfs2_dlm_lksb *lksb,
221                            u32 flags)
222 {
223         enum dlm_status status;
224         int o2dlm_flags = flags_to_o2dlm(flags);
225         int ret;
226
227         status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm,
228                            o2dlm_flags, o2dlm_unlock_ast_wrapper, lksb);
229         ret = dlm_status_to_errno(status);
230         return ret;
231 }
232
233 static int o2cb_dlm_lock_status(struct ocfs2_dlm_lksb *lksb)
234 {
235         return dlm_status_to_errno(lksb->lksb_o2dlm.status);
236 }
237
238 /*
239  * o2dlm aways has a "valid" LVB. If the dlm loses track of the LVB
240  * contents, it will zero out the LVB.  Thus the caller can always trust
241  * the contents.
242  */
243 static int o2cb_dlm_lvb_valid(struct ocfs2_dlm_lksb *lksb)
244 {
245         return 1;
246 }
247
248 static void *o2cb_dlm_lvb(struct ocfs2_dlm_lksb *lksb)
249 {
250         return (void *)(lksb->lksb_o2dlm.lvb);
251 }
252
253 static void o2cb_dump_lksb(struct ocfs2_dlm_lksb *lksb)
254 {
255         dlm_print_one_lock(lksb->lksb_o2dlm.lockid);
256 }
257
258 /*
259  * Called from the dlm when it's about to evict a node. This is how the
260  * classic stack signals node death.
261  */
262 static void o2dlm_eviction_cb(int node_num, void *data)
263 {
264         struct ocfs2_cluster_connection *conn = data;
265
266         mlog(ML_NOTICE, "o2dlm has evicted node %d from group %.*s\n",
267              node_num, conn->cc_namelen, conn->cc_name);
268
269         conn->cc_recovery_handler(node_num, conn->cc_recovery_data);
270 }
271
272 static int o2cb_cluster_connect(struct ocfs2_cluster_connection *conn)
273 {
274         int rc = 0;
275         u32 dlm_key;
276         struct dlm_ctxt *dlm;
277         struct o2dlm_private *priv;
278         struct dlm_protocol_version fs_version;
279
280         BUG_ON(conn == NULL);
281         BUG_ON(conn->cc_proto == NULL);
282
283         /* for now we only have one cluster/node, make sure we see it
284          * in the heartbeat universe */
285         if (!o2hb_check_local_node_heartbeating()) {
286                 if (o2hb_global_heartbeat_active())
287                         mlog(ML_ERROR, "Global heartbeat not started\n");
288                 rc = -EINVAL;
289                 goto out;
290         }
291
292         priv = kzalloc(sizeof(struct o2dlm_private), GFP_KERNEL);
293         if (!priv) {
294                 rc = -ENOMEM;
295                 goto out_free;
296         }
297
298         /* This just fills the structure in.  It is safe to pass conn. */
299         dlm_setup_eviction_cb(&priv->op_eviction_cb, o2dlm_eviction_cb,
300                               conn);
301
302         conn->cc_private = priv;
303
304         /* used by the dlm code to make message headers unique, each
305          * node in this domain must agree on this. */
306         dlm_key = crc32_le(0, conn->cc_name, conn->cc_namelen);
307         fs_version.pv_major = conn->cc_version.pv_major;
308         fs_version.pv_minor = conn->cc_version.pv_minor;
309
310         dlm = dlm_register_domain(conn->cc_name, dlm_key, &fs_version);
311         if (IS_ERR(dlm)) {
312                 rc = PTR_ERR(dlm);
313                 mlog_errno(rc);
314                 goto out_free;
315         }
316
317         conn->cc_version.pv_major = fs_version.pv_major;
318         conn->cc_version.pv_minor = fs_version.pv_minor;
319         conn->cc_lockspace = dlm;
320
321         dlm_register_eviction_cb(dlm, &priv->op_eviction_cb);
322
323 out_free:
324         if (rc && conn->cc_private)
325                 kfree(conn->cc_private);
326
327 out:
328         return rc;
329 }
330
331 static int o2cb_cluster_disconnect(struct ocfs2_cluster_connection *conn)
332 {
333         struct dlm_ctxt *dlm = conn->cc_lockspace;
334         struct o2dlm_private *priv = conn->cc_private;
335
336         dlm_unregister_eviction_cb(&priv->op_eviction_cb);
337         conn->cc_private = NULL;
338         kfree(priv);
339
340         dlm_unregister_domain(dlm);
341         conn->cc_lockspace = NULL;
342
343         return 0;
344 }
345
346 static int o2cb_cluster_this_node(unsigned int *node)
347 {
348         int node_num;
349
350         node_num = o2nm_this_node();
351         if (node_num == O2NM_INVALID_NODE_NUM)
352                 return -ENOENT;
353
354         if (node_num >= O2NM_MAX_NODES)
355                 return -EOVERFLOW;
356
357         *node = node_num;
358         return 0;
359 }
360
361 static struct ocfs2_stack_operations o2cb_stack_ops = {
362         .connect        = o2cb_cluster_connect,
363         .disconnect     = o2cb_cluster_disconnect,
364         .this_node      = o2cb_cluster_this_node,
365         .dlm_lock       = o2cb_dlm_lock,
366         .dlm_unlock     = o2cb_dlm_unlock,
367         .lock_status    = o2cb_dlm_lock_status,
368         .lvb_valid      = o2cb_dlm_lvb_valid,
369         .lock_lvb       = o2cb_dlm_lvb,
370         .dump_lksb      = o2cb_dump_lksb,
371 };
372
373 static struct ocfs2_stack_plugin o2cb_stack = {
374         .sp_name        = "o2cb",
375         .sp_ops         = &o2cb_stack_ops,
376         .sp_owner       = THIS_MODULE,
377 };
378
379 static int __init o2cb_stack_init(void)
380 {
381         return ocfs2_stack_glue_register(&o2cb_stack);
382 }
383
384 static void __exit o2cb_stack_exit(void)
385 {
386         ocfs2_stack_glue_unregister(&o2cb_stack);
387 }
388
389 MODULE_AUTHOR("Oracle");
390 MODULE_DESCRIPTION("ocfs2 driver for the classic o2cb stack");
391 MODULE_LICENSE("GPL");
392 module_init(o2cb_stack_init);
393 module_exit(o2cb_stack_exit);