xref: /netbsd-src/external/cddl/osnet/dist/uts/common/fs/zfs/vdev_file.c (revision ba2539a9805a0544ff82c0003cc02fe1eee5603d)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2011, 2015 by Delphix. All rights reserved.
24  */
25 
26 #include <sys/zfs_context.h>
27 #include <sys/spa.h>
28 #include <sys/vdev_file.h>
29 #include <sys/vdev_impl.h>
30 #include <sys/zio.h>
31 #include <sys/fs/zfs.h>
32 #include <sys/fm/fs/zfs.h>
33 
34 /*
35  * Virtual device vector for files.
36  */
37 
38 static void
vdev_file_hold(vdev_t * vd)39 vdev_file_hold(vdev_t *vd)
40 {
41 	ASSERT(vd->vdev_path != NULL);
42 }
43 
44 static void
vdev_file_rele(vdev_t * vd)45 vdev_file_rele(vdev_t *vd)
46 {
47 	ASSERT(vd->vdev_path != NULL);
48 }
49 
50 static int
vdev_file_open(vdev_t * vd,uint64_t * psize,uint64_t * max_psize,uint64_t * logical_ashift,uint64_t * physical_ashift)51 vdev_file_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize,
52     uint64_t *logical_ashift, uint64_t *physical_ashift)
53 {
54 	vdev_file_t *vf;
55 	vnode_t *vp;
56 	vattr_t vattr;
57 	int error;
58 
59 	/*
60 	 * We must have a pathname, and it must be absolute.
61 	 */
62 	if (vd->vdev_path == NULL || vd->vdev_path[0] != '/') {
63 		vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
64 		return (SET_ERROR(EINVAL));
65 	}
66 
67 	/*
68 	 * Reopen the device if it's not currently open.  Otherwise,
69 	 * just update the physical size of the device.
70 	 */
71 	if (vd->vdev_tsd != NULL) {
72 		ASSERT(vd->vdev_reopening);
73 		vf = vd->vdev_tsd;
74 		vp = vf->vf_vnode;
75 		goto skip_open;
76 	}
77 
78 	vf = vd->vdev_tsd = kmem_zalloc(sizeof (vdev_file_t), KM_SLEEP);
79 
80 	/*
81 	 * We always open the files from the root of the global zone, even if
82 	 * we're in a local zone.  If the user has gotten to this point, the
83 	 * administrator has already decided that the pool should be available
84 	 * to local zone users, so the underlying devices should be as well.
85 	 */
86 	ASSERT(vd->vdev_path != NULL && vd->vdev_path[0] == '/');
87 	error = vn_openat(vd->vdev_path + 1, UIO_SYSSPACE,
88 	    spa_mode(vd->vdev_spa) | FOFFMAX, 0, &vp, 0, 0, rootdir, -1);
89 
90 	if (error) {
91 		vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
92 		kmem_free(vd->vdev_tsd, sizeof (vdev_file_t));
93 		vd->vdev_tsd = NULL;
94 		return (error);
95 	}
96 
97 	vf->vf_vnode = vp;
98 
99 #ifdef _KERNEL
100 	/*
101 	 * Make sure it's a regular file.
102 	 */
103 	if (vp->v_type != VREG) {
104 		(void) VOP_CLOSE(vp, spa_mode(vd->vdev_spa), 1, 0, kcred, NULL);
105 		kmem_free(vd->vdev_tsd, sizeof (vdev_file_t));
106 		vd->vdev_tsd = NULL;
107 		vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
108 		return (SET_ERROR(ENODEV));
109 	}
110 #endif	/* _KERNEL */
111 
112 skip_open:
113 	/*
114 	 * Determine the physical size of the file.
115 	 */
116 	vattr.va_mask = AT_SIZE;
117 #ifdef __FreeBSD__
118 	vn_lock(vp, LK_SHARED | LK_RETRY);
119 	error = VOP_GETATTR(vp, &vattr, kcred);
120 	VOP_UNLOCK(vp, 0);
121 #endif
122 #ifdef __NetBSD__
123 	error = VOP_GETATTR(vp, &vattr, 0, kcred, NULL);
124 #endif
125 	if (error) {
126 		(void) VOP_CLOSE(vp, spa_mode(vd->vdev_spa), 1, 0, kcred, NULL);
127 		vd->vdev_stat.vs_aux = VDEV_AUX_OPEN_FAILED;
128 		kmem_free(vd->vdev_tsd, sizeof (vdev_file_t));
129 		vd->vdev_tsd = NULL;
130 		return (error);
131 	}
132 
133 	vd->vdev_notrim = B_TRUE;
134 
135 	*max_psize = *psize = vattr.va_size;
136 	*logical_ashift = SPA_MINBLOCKSHIFT;
137 	*physical_ashift = SPA_MINBLOCKSHIFT;
138 
139 	return (0);
140 }
141 
142 static void
vdev_file_close(vdev_t * vd)143 vdev_file_close(vdev_t *vd)
144 {
145 	vdev_file_t *vf = vd->vdev_tsd;
146 
147 	if (vd->vdev_reopening || vf == NULL)
148 		return;
149 
150 	if (vf->vf_vnode != NULL) {
151 		(void) VOP_CLOSE(vf->vf_vnode, spa_mode(vd->vdev_spa), 1, 0,
152 		    kcred, NULL);
153 	}
154 
155 	vd->vdev_delayed_close = B_FALSE;
156 	kmem_free(vf, sizeof (vdev_file_t));
157 	vd->vdev_tsd = NULL;
158 }
159 
160 static void
vdev_file_io_start(zio_t * zio)161 vdev_file_io_start(zio_t *zio)
162 {
163 	vdev_t *vd = zio->io_vd;
164 	vdev_file_t *vf;
165 	vnode_t *vp;
166 	ssize_t resid;
167 
168 	if (!vdev_readable(vd)) {
169 		zio->io_error = SET_ERROR(ENXIO);
170 		zio_interrupt(zio);
171 		return;
172 	}
173 
174 	vf = vd->vdev_tsd;
175 	vp = vf->vf_vnode;
176 
177 	if (zio->io_type == ZIO_TYPE_IOCTL) {
178 		switch (zio->io_cmd) {
179 		case DKIOCFLUSHWRITECACHE:
180 			zio->io_error = VOP_FSYNC(vp, FSYNC | FDSYNC,
181 			    kcred, NULL);
182 			break;
183 		default:
184 			zio->io_error = SET_ERROR(ENOTSUP);
185 		}
186 
187 		zio_execute(zio);
188 		return;
189 	}
190 
191 	ASSERT(zio->io_type == ZIO_TYPE_READ || zio->io_type == ZIO_TYPE_WRITE);
192 	zio->io_target_timestamp = zio_handle_io_delay(zio);
193 
194 	zio->io_error = vn_rdwr(zio->io_type == ZIO_TYPE_READ ?
195 	    UIO_READ : UIO_WRITE, vp, zio->io_data, zio->io_size,
196 	    zio->io_offset, UIO_SYSSPACE, 0, RLIM64_INFINITY, kcred, &resid);
197 
198 	if (resid != 0 && zio->io_error == 0)
199 		zio->io_error = ENOSPC;
200 
201 	zio_delay_interrupt(zio);
202 
203 #ifdef illumos
204 	VERIFY3U(taskq_dispatch(system_taskq, vdev_file_io_strategy, bp,
205 	    TQ_SLEEP), !=, 0);
206 #endif
207 }
208 
209 /* ARGSUSED */
210 static void
vdev_file_io_done(zio_t * zio)211 vdev_file_io_done(zio_t *zio)
212 {
213 }
214 
215 vdev_ops_t vdev_file_ops = {
216 	vdev_file_open,
217 	vdev_file_close,
218 	vdev_default_asize,
219 	vdev_file_io_start,
220 	vdev_file_io_done,
221 	NULL,
222 	vdev_file_hold,
223 	vdev_file_rele,
224 	VDEV_TYPE_FILE,		/* name of this vdev type */
225 	B_TRUE			/* leaf vdev */
226 };
227 
228 /*
229  * From userland we access disks just like files.
230  */
231 #ifndef _KERNEL
232 
233 vdev_ops_t vdev_disk_ops = {
234 	vdev_file_open,
235 	vdev_file_close,
236 	vdev_default_asize,
237 	vdev_file_io_start,
238 	vdev_file_io_done,
239 	NULL,
240 	vdev_file_hold,
241 	vdev_file_rele,
242 	VDEV_TYPE_DISK,		/* name of this vdev type */
243 	B_TRUE			/* leaf vdev */
244 };
245 
246 #endif
247