1 /*
2  * Copyright (c) 2007-2008 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * $DragonFly: src/sys/vfs/hammer/hammer_transaction.c,v 1.25 2008/09/23 21:03:52 dillon Exp $
35  */
36 
37 #include "hammer.h"
38 
39 static hammer_tid_t hammer_alloc_tid(hammer_mount_t hmp, int count);
40 
41 
42 /*
43  * Start a standard transaction.
44  */
45 void
46 hammer_start_transaction(struct hammer_transaction *trans,
47 			 struct hammer_mount *hmp)
48 {
49 	struct timeval tv;
50 	int error;
51 
52 	trans->type = HAMMER_TRANS_STD;
53 	trans->hmp = hmp;
54 	trans->rootvol = hammer_get_root_volume(hmp, &error);
55 	KKASSERT(error == 0);
56 	trans->tid = 0;
57 	trans->sync_lock_refs = 0;
58 	trans->flags = 0;
59 
60 	getmicrotime(&tv);
61 	trans->time = (unsigned long)tv.tv_sec * 1000000ULL + tv.tv_usec;
62 	trans->time32 = (u_int32_t)tv.tv_sec;
63 }
64 
65 /*
66  * Start a simple read-only transaction.  This will not stall.
67  */
68 void
69 hammer_simple_transaction(struct hammer_transaction *trans,
70 			  struct hammer_mount *hmp)
71 {
72 	struct timeval tv;
73 	int error;
74 
75 	trans->type = HAMMER_TRANS_RO;
76 	trans->hmp = hmp;
77 	trans->rootvol = hammer_get_root_volume(hmp, &error);
78 	KKASSERT(error == 0);
79 	trans->tid = 0;
80 	trans->sync_lock_refs = 0;
81 	trans->flags = 0;
82 
83 	getmicrotime(&tv);
84 	trans->time = (unsigned long)tv.tv_sec * 1000000ULL + tv.tv_usec;
85 	trans->time32 = (u_int32_t)tv.tv_sec;
86 }
87 
88 /*
89  * Start a transaction using a particular TID.  Used by the sync code.
90  * This does not stall.
91  *
92  * This routine may only be called from the flusher thread.  We predispose
93  * sync_lock_refs, implying serialization against the synchronization stage
94  * (which the flusher is responsible for).
95  */
96 void
97 hammer_start_transaction_fls(struct hammer_transaction *trans,
98 			     struct hammer_mount *hmp)
99 {
100 	struct timeval tv;
101 	int error;
102 
103 	bzero(trans, sizeof(*trans));
104 
105 	trans->type = HAMMER_TRANS_FLS;
106 	trans->hmp = hmp;
107 	trans->rootvol = hammer_get_root_volume(hmp, &error);
108 	KKASSERT(error == 0);
109 	trans->tid = hammer_alloc_tid(hmp, 1);
110 	trans->sync_lock_refs = 1;
111 	trans->flags = 0;
112 
113 	getmicrotime(&tv);
114 	trans->time = (unsigned long)tv.tv_sec * 1000000ULL + tv.tv_usec;
115 	trans->time32 = (u_int32_t)tv.tv_sec;
116 }
117 
118 void
119 hammer_done_transaction(struct hammer_transaction *trans)
120 {
121 	hammer_mount_t hmp = trans->hmp;
122 	int expected_lock_refs;
123 
124 	hammer_rel_volume(trans->rootvol, 0);
125 	trans->rootvol = NULL;
126 	expected_lock_refs = (trans->type == HAMMER_TRANS_FLS) ? 1 : 0;
127 	KKASSERT(trans->sync_lock_refs == expected_lock_refs);
128 	trans->sync_lock_refs = 0;
129 	if (trans->type != HAMMER_TRANS_FLS) {
130 		if (trans->flags & HAMMER_TRANSF_NEWINODE)
131 			hammer_inode_waitreclaims(hmp);
132 		else if (trans->flags & HAMMER_TRANSF_DIDIO)
133 			hammer_inode_waithard(hmp);
134 	}
135 }
136 
137 /*
138  * Allocate (count) TIDs.  If running in multi-master mode the returned
139  * base will be aligned to a 16-count plus the master id (0-15).
140  * Multi-master mode allows non-conflicting to run and new objects to be
141  * created on multiple masters in parallel.  The transaction id identifies
142  * the original master.  The object_id is also subject to this rule in
143  * order to allow objects to be created on multiple masters in parallel.
144  *
145  * Directories may pre-allocate a large number of object ids (100,000).
146  *
147  * NOTE: There is no longer a requirement that successive transaction
148  * ids be 2 apart for separator generation.
149  */
150 static hammer_tid_t
151 hammer_alloc_tid(hammer_mount_t hmp, int count)
152 {
153 	hammer_tid_t tid;
154 
155 	if (hmp->master_id < 0) {
156 		tid = hmp->next_tid + 1;
157 		hmp->next_tid = tid + count;
158 	} else {
159 		tid = (hmp->next_tid + HAMMER_MAX_MASTERS) &
160 		      ~(hammer_tid_t)(HAMMER_MAX_MASTERS - 1);
161 		hmp->next_tid = tid + count * HAMMER_MAX_MASTERS;
162 		tid |= hmp->master_id;
163 	}
164 	if (tid >= 0xFFFFFFFFFF000000ULL)
165 		panic("hammer_start_transaction: Ran out of TIDs!");
166 	if (hammer_debug_tid)
167 		kprintf("alloc_tid %016llx\n", tid);
168 	return(tid);
169 }
170 
171 /*
172  * Allocate an object id
173  */
174 hammer_tid_t
175 hammer_alloc_objid(hammer_mount_t hmp, hammer_inode_t dip)
176 {
177 	hammer_objid_cache_t ocp;
178 	hammer_tid_t tid;
179 
180 	while ((ocp = dip->objid_cache) == NULL) {
181 		if (hmp->objid_cache_count < OBJID_CACHE_SIZE) {
182 			ocp = kmalloc(sizeof(*ocp), hmp->m_misc,
183 				      M_WAITOK|M_ZERO);
184 			ocp->next_tid = hammer_alloc_tid(hmp, OBJID_CACHE_BULK);
185 			ocp->count = OBJID_CACHE_BULK;
186 			TAILQ_INSERT_HEAD(&hmp->objid_cache_list, ocp, entry);
187 			++hmp->objid_cache_count;
188 			/* may have blocked, recheck */
189 			if (dip->objid_cache == NULL) {
190 				dip->objid_cache = ocp;
191 				ocp->dip = dip;
192 			}
193 		} else {
194 			ocp = TAILQ_FIRST(&hmp->objid_cache_list);
195 			if (ocp->dip)
196 				ocp->dip->objid_cache = NULL;
197 			dip->objid_cache = ocp;
198 			ocp->dip = dip;
199 		}
200 	}
201 	TAILQ_REMOVE(&hmp->objid_cache_list, ocp, entry);
202 
203 	/*
204 	 * The TID is incremented by 1 or by 16 depending what mode the
205 	 * mount is operating in.
206 	 */
207 	tid = ocp->next_tid;
208 	ocp->next_tid += (hmp->master_id < 0) ? 1 : HAMMER_MAX_MASTERS;
209 
210 	if (--ocp->count == 0) {
211 		dip->objid_cache = NULL;
212 		--hmp->objid_cache_count;
213 		ocp->dip = NULL;
214 		kfree(ocp, hmp->m_misc);
215 	} else {
216 		TAILQ_INSERT_TAIL(&hmp->objid_cache_list, ocp, entry);
217 	}
218 	return(tid);
219 }
220 
221 void
222 hammer_clear_objid(hammer_inode_t dip)
223 {
224 	hammer_objid_cache_t ocp;
225 
226 	if ((ocp = dip->objid_cache) != NULL) {
227 		dip->objid_cache = NULL;
228 		ocp->dip = NULL;
229 		TAILQ_REMOVE(&dip->hmp->objid_cache_list, ocp, entry);
230 		TAILQ_INSERT_HEAD(&dip->hmp->objid_cache_list, ocp, entry);
231 	}
232 }
233 
234 void
235 hammer_destroy_objid_cache(hammer_mount_t hmp)
236 {
237 	hammer_objid_cache_t ocp;
238 
239 	while ((ocp = TAILQ_FIRST(&hmp->objid_cache_list)) != NULL) {
240 		TAILQ_REMOVE(&hmp->objid_cache_list, ocp, entry);
241 		if (ocp->dip)
242 			ocp->dip->objid_cache = NULL;
243 		kfree(ocp, hmp->m_misc);
244 	}
245 }
246 
247