xref: /freebsd/sys/geom/geom_vfs.c (revision 9162f64b58d01ec01481d60b6cdc06ffd8e8c7fc)
1 /*-
2  * Copyright (c) 2004 Poul-Henning Kamp
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bio.h>
33 #include <sys/kernel.h>
34 #include <sys/malloc.h>
35 #include <sys/vnode.h>
36 #include <sys/mount.h>	/* XXX Temporary for VFS_LOCK_GIANT */
37 
38 #include <geom/geom.h>
39 #include <geom/geom_vfs.h>
40 
41 /*
42  * subroutines for use by filesystems.
43  *
44  * XXX: should maybe live somewhere else ?
45  */
46 #include <sys/buf.h>
47 
48 static struct buf_ops __g_vfs_bufops = {
49 	.bop_name =	"GEOM_VFS",
50 	.bop_write =	bufwrite,
51 	.bop_strategy =	g_vfs_strategy,
52 	.bop_sync =	bufsync,
53 	.bop_bdflush =	bufbdflush
54 };
55 
56 struct buf_ops *g_vfs_bufops = &__g_vfs_bufops;
57 
58 static g_orphan_t g_vfs_orphan;
59 
60 static struct g_class g_vfs_class = {
61 	.name =		"VFS",
62 	.version =	G_VERSION,
63 	.orphan =	g_vfs_orphan,
64 };
65 
66 DECLARE_GEOM_CLASS(g_vfs_class, g_vfs);
67 
68 static void
69 g_vfs_done(struct bio *bip)
70 {
71 	struct buf *bp;
72 	int vfslocked;
73 
74 	if (bip->bio_error) {
75 		printf("g_vfs_done():");
76 		g_print_bio(bip);
77 		printf("error = %d\n", bip->bio_error);
78 	}
79 	bp = bip->bio_caller2;
80 	bp->b_error = bip->bio_error;
81 	bp->b_ioflags = bip->bio_flags;
82 	if (bip->bio_error)
83 		bp->b_ioflags |= BIO_ERROR;
84 	bp->b_resid = bp->b_bcount - bip->bio_completed;
85 	g_destroy_bio(bip);
86 	vfslocked = VFS_LOCK_GIANT(((struct mount *)NULL));
87 	bufdone(bp);
88 	VFS_UNLOCK_GIANT(vfslocked);
89 }
90 
91 void
92 g_vfs_strategy(struct bufobj *bo, struct buf *bp)
93 {
94 	struct g_consumer *cp;
95 	struct bio *bip;
96 	int vfslocked;
97 
98 	cp = bo->bo_private;
99 	G_VALID_CONSUMER(cp);
100 
101 	/*
102 	 * If the the provider has orphaned us, just return EXIO.
103 	 */
104 	if (cp->provider == NULL) {
105 		bp->b_error = ENXIO;
106 		bp->b_ioflags |= BIO_ERROR;
107 		vfslocked = VFS_LOCK_GIANT(((struct mount *)NULL));
108 		bufdone(bp);
109 		VFS_UNLOCK_GIANT(vfslocked);
110 		return;
111 	}
112 
113 	bip = g_alloc_bio();
114 	bip->bio_cmd = bp->b_iocmd;
115 	bip->bio_offset = bp->b_iooffset;
116 	bip->bio_data = bp->b_data;
117 	bip->bio_done = g_vfs_done;
118 	bip->bio_caller2 = bp;
119 	bip->bio_length = bp->b_bcount;
120 	g_io_request(bip, cp);
121 }
122 
123 static void
124 g_vfs_orphan(struct g_consumer *cp)
125 {
126 	struct g_geom *gp;
127 	struct bufobj *bo;
128 
129 	g_topology_assert();
130 
131 	gp = cp->geom;
132 	bo = gp->softc;
133 	g_trace(G_T_TOPOLOGY, "g_vfs_orphan(%p(%s))", cp, gp->name);
134 	if (cp->acr > 0 || cp->acw > 0 || cp->ace > 0)
135 		g_access(cp, -cp->acr, -cp->acw, -cp->ace);
136 	g_detach(cp);
137 
138 	/*
139 	 * Do not destroy the geom. Filesystem will do this during unmount.
140 	 */
141 }
142 
143 int
144 g_vfs_open(struct vnode *vp, struct g_consumer **cpp, const char *fsname, int wr)
145 {
146 	struct g_geom *gp;
147 	struct g_provider *pp;
148 	struct g_consumer *cp;
149 	struct bufobj *bo;
150 	int vfslocked;
151 	int error;
152 
153 	g_topology_assert();
154 
155 	*cpp = NULL;
156 	pp = g_dev_getprovider(vp->v_rdev);
157 	if (pp == NULL)
158 		return (ENOENT);
159 	gp = g_new_geomf(&g_vfs_class, "%s.%s", fsname, pp->name);
160 	cp = g_new_consumer(gp);
161 	g_attach(cp, pp);
162 	error = g_access(cp, 1, wr, 1);
163 	if (error) {
164 		g_wither_geom(gp, ENXIO);
165 		return (error);
166 	}
167 	vfslocked = VFS_LOCK_GIANT(vp->v_mount);
168 	vnode_create_vobject(vp, pp->mediasize, curthread);
169 	VFS_UNLOCK_GIANT(vfslocked);
170 	*cpp = cp;
171 	bo = &vp->v_bufobj;
172 	bo->bo_ops = g_vfs_bufops;
173 	bo->bo_private = cp;
174 	bo->bo_bsize = pp->sectorsize;
175 	gp->softc = bo;
176 
177 	return (error);
178 }
179 
180 void
181 g_vfs_close(struct g_consumer *cp)
182 {
183 	struct g_geom *gp;
184 	struct bufobj *bo;
185 
186 	g_topology_assert();
187 
188 	gp = cp->geom;
189 	bo = gp->softc;
190 	bufobj_invalbuf(bo, V_SAVE, 0, 0);
191 	g_wither_geom_close(gp, ENXIO);
192 }
193