xref: /dflybsd-src/sys/vfs/hammer/hammer_transaction.c (revision d54592ee9e96c920b951af2e00cd72c0081ccae3)
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 1.24 2008/07/19 18:44:49 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 
59 	getmicrotime(&tv);
60 	trans->time = (unsigned long)tv.tv_sec * 1000000ULL + tv.tv_usec;
61 	trans->time32 = (u_int32_t)tv.tv_sec;
62 }
63 
64 /*
65  * Start a simple read-only transaction.  This will not stall.
66  */
67 void
68 hammer_simple_transaction(struct hammer_transaction *trans,
69 			  struct hammer_mount *hmp)
70 {
71 	struct timeval tv;
72 	int error;
73 
74 	trans->type = HAMMER_TRANS_RO;
75 	trans->hmp = hmp;
76 	trans->rootvol = hammer_get_root_volume(hmp, &error);
77 	KKASSERT(error == 0);
78 	trans->tid = 0;
79 	trans->sync_lock_refs = 0;
80 
81 	getmicrotime(&tv);
82 	trans->time = (unsigned long)tv.tv_sec * 1000000ULL + tv.tv_usec;
83 	trans->time32 = (u_int32_t)tv.tv_sec;
84 }
85 
86 /*
87  * Start a transaction using a particular TID.  Used by the sync code.
88  * This does not stall.
89  *
90  * This routine may only be called from the flusher thread.  We predispose
91  * sync_lock_refs, implying serialization against the synchronization stage
92  * (which the flusher is responsible for).
93  */
94 void
95 hammer_start_transaction_fls(struct hammer_transaction *trans,
96 			     struct hammer_mount *hmp)
97 {
98 	struct timeval tv;
99 	int error;
100 
101 	bzero(trans, sizeof(*trans));
102 
103 	trans->type = HAMMER_TRANS_FLS;
104 	trans->hmp = hmp;
105 	trans->rootvol = hammer_get_root_volume(hmp, &error);
106 	KKASSERT(error == 0);
107 	trans->tid = hammer_alloc_tid(hmp, 1);
108 	trans->sync_lock_refs = 1;
109 
110 	getmicrotime(&tv);
111 	trans->time = (unsigned long)tv.tv_sec * 1000000ULL + tv.tv_usec;
112 	trans->time32 = (u_int32_t)tv.tv_sec;
113 }
114 
115 void
116 hammer_done_transaction(struct hammer_transaction *trans)
117 {
118 	int expected_lock_refs;
119 
120 	hammer_rel_volume(trans->rootvol, 0);
121 	trans->rootvol = NULL;
122 	expected_lock_refs = (trans->type == HAMMER_TRANS_FLS) ? 1 : 0;
123 	KKASSERT(trans->sync_lock_refs == expected_lock_refs);
124 	trans->sync_lock_refs = 0;
125 }
126 
127 /*
128  * Allocate (count) TIDs.  If running in multi-master mode the returned
129  * base will be aligned to a 16-count plus the master id (0-15).
130  * Multi-master mode allows non-conflicting to run and new objects to be
131  * created on multiple masters in parallel.  The transaction id identifies
132  * the original master.  The object_id is also subject to this rule in
133  * order to allow objects to be created on multiple masters in parallel.
134  *
135  * Directories may pre-allocate a large number of object ids (100,000).
136  *
137  * NOTE: There is no longer a requirement that successive transaction
138  * ids be 2 apart for separator generation.
139  */
140 static hammer_tid_t
141 hammer_alloc_tid(hammer_mount_t hmp, int count)
142 {
143 	hammer_tid_t tid;
144 
145 	if (hmp->master_id < 0) {
146 		tid = hmp->next_tid + 1;
147 		hmp->next_tid = tid + count;
148 	} else {
149 		tid = (hmp->next_tid + HAMMER_MAX_MASTERS) &
150 		      ~(hammer_tid_t)(HAMMER_MAX_MASTERS - 1);
151 		hmp->next_tid = tid + count * HAMMER_MAX_MASTERS;
152 		tid |= hmp->master_id;
153 	}
154 	if (tid >= 0xFFFFFFFFFF000000ULL)
155 		panic("hammer_start_transaction: Ran out of TIDs!");
156 	if (hammer_debug_tid)
157 		kprintf("alloc_tid %016llx\n", tid);
158 	return(tid);
159 }
160 
161 /*
162  * Allocate an object id
163  */
164 hammer_tid_t
165 hammer_alloc_objid(hammer_mount_t hmp, hammer_inode_t dip)
166 {
167 	hammer_objid_cache_t ocp;
168 	hammer_tid_t tid;
169 
170 	while ((ocp = dip->objid_cache) == NULL) {
171 		if (hmp->objid_cache_count < OBJID_CACHE_SIZE) {
172 			ocp = kmalloc(sizeof(*ocp), M_HAMMER, M_WAITOK|M_ZERO);
173 			ocp->next_tid = hammer_alloc_tid(hmp, OBJID_CACHE_BULK);
174 			ocp->count = OBJID_CACHE_BULK;
175 			TAILQ_INSERT_HEAD(&hmp->objid_cache_list, ocp, entry);
176 			++hmp->objid_cache_count;
177 			/* may have blocked, recheck */
178 			if (dip->objid_cache == NULL) {
179 				dip->objid_cache = ocp;
180 				ocp->dip = dip;
181 			}
182 		} else {
183 			ocp = TAILQ_FIRST(&hmp->objid_cache_list);
184 			if (ocp->dip)
185 				ocp->dip->objid_cache = NULL;
186 			dip->objid_cache = ocp;
187 			ocp->dip = dip;
188 		}
189 	}
190 	TAILQ_REMOVE(&hmp->objid_cache_list, ocp, entry);
191 
192 	/*
193 	 * The TID is incremented by 1 or by 16 depending what mode the
194 	 * mount is operating in.
195 	 */
196 	tid = ocp->next_tid;
197 	ocp->next_tid += (hmp->master_id < 0) ? 1 : HAMMER_MAX_MASTERS;
198 
199 	if (--ocp->count == 0) {
200 		dip->objid_cache = NULL;
201 		--hmp->objid_cache_count;
202 		ocp->dip = NULL;
203 		kfree(ocp, M_HAMMER);
204 	} else {
205 		TAILQ_INSERT_TAIL(&hmp->objid_cache_list, ocp, entry);
206 	}
207 	return(tid);
208 }
209 
210 void
211 hammer_clear_objid(hammer_inode_t dip)
212 {
213 	hammer_objid_cache_t ocp;
214 
215 	if ((ocp = dip->objid_cache) != NULL) {
216 		dip->objid_cache = NULL;
217 		ocp->dip = NULL;
218 		TAILQ_REMOVE(&dip->hmp->objid_cache_list, ocp, entry);
219 		TAILQ_INSERT_HEAD(&dip->hmp->objid_cache_list, ocp, entry);
220 	}
221 }
222 
223 void
224 hammer_destroy_objid_cache(hammer_mount_t hmp)
225 {
226 	hammer_objid_cache_t ocp;
227 
228 	while ((ocp = TAILQ_FIRST(&hmp->objid_cache_list)) != NULL) {
229 		TAILQ_REMOVE(&hmp->objid_cache_list, ocp, entry);
230 		if (ocp->dip)
231 			ocp->dip->objid_cache = NULL;
232 		kfree(ocp, M_HAMMER);
233 	}
234 }
235 
236