xref: /freebsd-src/sys/contrib/openzfs/module/os/freebsd/zfs/vdev_label_os.c (revision 9d6043f980a2ee424976c71c437888c9095f8142)
1eda14cbcSMatt Macy /*
2eda14cbcSMatt Macy  * CDDL HEADER START
3eda14cbcSMatt Macy  *
4eda14cbcSMatt Macy  * The contents of this file are subject to the terms of the
5eda14cbcSMatt Macy  * Common Development and Distribution License (the "License").
6eda14cbcSMatt Macy  * You may not use this file except in compliance with the License.
7eda14cbcSMatt Macy  *
8eda14cbcSMatt Macy  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9271171e0SMartin Matuska  * or https://opensource.org/licenses/CDDL-1.0.
10eda14cbcSMatt Macy  * See the License for the specific language governing permissions
11eda14cbcSMatt Macy  * and limitations under the License.
12eda14cbcSMatt Macy  *
13eda14cbcSMatt Macy  * When distributing Covered Code, include this CDDL HEADER in each
14eda14cbcSMatt Macy  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15eda14cbcSMatt Macy  * If applicable, add the following below this CDDL HEADER, with the
16eda14cbcSMatt Macy  * fields enclosed by brackets "[]" replaced with your own identifying
17eda14cbcSMatt Macy  * information: Portions Copyright [yyyy] [name of copyright owner]
18eda14cbcSMatt Macy  *
19eda14cbcSMatt Macy  * CDDL HEADER END
20eda14cbcSMatt Macy  */
21eda14cbcSMatt Macy 
22eda14cbcSMatt Macy #include <sys/zfs_context.h>
23eda14cbcSMatt Macy #include <sys/spa.h>
24eda14cbcSMatt Macy #include <sys/spa_impl.h>
25eda14cbcSMatt Macy #include <sys/dmu.h>
26eda14cbcSMatt Macy #include <sys/zap.h>
27eda14cbcSMatt Macy #include <sys/vdev.h>
28eda14cbcSMatt Macy #include <sys/vdev_os.h>
29eda14cbcSMatt Macy #include <sys/vdev_impl.h>
30eda14cbcSMatt Macy #include <sys/uberblock_impl.h>
31eda14cbcSMatt Macy #include <sys/metaslab.h>
32eda14cbcSMatt Macy #include <sys/metaslab_impl.h>
33eda14cbcSMatt Macy #include <sys/zio.h>
34eda14cbcSMatt Macy #include <sys/dsl_scan.h>
35eda14cbcSMatt Macy #include <sys/abd.h>
36eda14cbcSMatt Macy #include <sys/fs/zfs.h>
37eda14cbcSMatt Macy 
38eda14cbcSMatt Macy int
39eda14cbcSMatt Macy vdev_label_write_pad2(vdev_t *vd, const char *buf, size_t size)
40eda14cbcSMatt Macy {
41eda14cbcSMatt Macy 	spa_t *spa = vd->vdev_spa;
42eda14cbcSMatt Macy 	zio_t *zio;
43eda14cbcSMatt Macy 	abd_t *pad2;
44eda14cbcSMatt Macy 	int flags = ZIO_FLAG_CONFIG_WRITER | ZIO_FLAG_CANFAIL;
45eda14cbcSMatt Macy 	int error;
46eda14cbcSMatt Macy 
47eda14cbcSMatt Macy 	if (size > VDEV_PAD_SIZE)
48eda14cbcSMatt Macy 		return (EINVAL);
49eda14cbcSMatt Macy 
50eda14cbcSMatt Macy 	if (!vd->vdev_ops->vdev_op_leaf)
51eda14cbcSMatt Macy 		return (ENODEV);
52eda14cbcSMatt Macy 	if (vdev_is_dead(vd))
53eda14cbcSMatt Macy 		return (ENXIO);
54eda14cbcSMatt Macy 
5516038816SMartin Matuska 	ASSERT3U(spa_config_held(spa, SCL_ALL, RW_WRITER), ==, SCL_ALL);
56eda14cbcSMatt Macy 
57eda14cbcSMatt Macy 	pad2 = abd_alloc_for_io(VDEV_PAD_SIZE, B_TRUE);
58eda14cbcSMatt Macy 	abd_copy_from_buf(pad2, buf, size);
59a2b560ccSMartin Matuska 	abd_zero_off(pad2, size, VDEV_PAD_SIZE - size);
60eda14cbcSMatt Macy 
61eda14cbcSMatt Macy retry:
62eda14cbcSMatt Macy 	zio = zio_root(spa, NULL, NULL, flags);
63eda14cbcSMatt Macy 	vdev_label_write(zio, vd, 0, pad2,
64eda14cbcSMatt Macy 	    offsetof(vdev_label_t, vl_be),
65eda14cbcSMatt Macy 	    VDEV_PAD_SIZE, NULL, NULL, flags);
66eda14cbcSMatt Macy 	error = zio_wait(zio);
67eda14cbcSMatt Macy 	if (error != 0 && !(flags & ZIO_FLAG_TRYHARD)) {
68eda14cbcSMatt Macy 		flags |= ZIO_FLAG_TRYHARD;
69eda14cbcSMatt Macy 		goto retry;
70eda14cbcSMatt Macy 	}
71eda14cbcSMatt Macy 
72eda14cbcSMatt Macy 	abd_free(pad2);
73eda14cbcSMatt Macy 	return (error);
74eda14cbcSMatt Macy }
75e716630dSMartin Matuska 
76e716630dSMartin Matuska static void
77e716630dSMartin Matuska vdev_child_done(zio_t *zio)
78e716630dSMartin Matuska {
79e716630dSMartin Matuska 	zio_t *pio = zio->io_private;
80e716630dSMartin Matuska 
81e716630dSMartin Matuska 	mutex_enter(&pio->io_lock);
82e716630dSMartin Matuska 	pio->io_error = zio_worst_error(pio->io_error, zio->io_error);
83e716630dSMartin Matuska 	mutex_exit(&pio->io_lock);
84e716630dSMartin Matuska }
85e716630dSMartin Matuska 
86e716630dSMartin Matuska /*
87e716630dSMartin Matuska  * Check if the reserved boot area is in-use.
88e716630dSMartin Matuska  *
89e716630dSMartin Matuska  * When booting FreeBSD with an MBR partition with ZFS, the zfsboot file
90e716630dSMartin Matuska  * (which understands the ZFS file system) is written to the ZFS BOOT
91e716630dSMartin Matuska  * reserve area (at offset 512K). We check for that here before attaching
92e716630dSMartin Matuska  * a disk to raidz which would then corrupt this boot data.
93e716630dSMartin Matuska  */
94e716630dSMartin Matuska int
95e716630dSMartin Matuska vdev_check_boot_reserve(spa_t *spa, vdev_t *childvd)
96e716630dSMartin Matuska {
97e716630dSMartin Matuska 	ASSERT(childvd->vdev_ops->vdev_op_leaf);
98e716630dSMartin Matuska 
99*9d6043f9SMartin Matuska 	size_t size = 1ULL << childvd->vdev_top->vdev_ashift;
100e716630dSMartin Matuska 	abd_t *abd = abd_alloc_linear(size, B_FALSE);
101e716630dSMartin Matuska 
102e716630dSMartin Matuska 	zio_t *pio = zio_root(spa, NULL, NULL, 0);
103e716630dSMartin Matuska 	/*
104e716630dSMartin Matuska 	 * Note: zio_vdev_child_io() adds VDEV_LABEL_START_SIZE to the offset
105e716630dSMartin Matuska 	 * to calculate the physical offset to write to.  Passing in a negative
106e716630dSMartin Matuska 	 * offset lets us access the boot area.
107e716630dSMartin Matuska 	 */
108e716630dSMartin Matuska 	zio_nowait(zio_vdev_child_io(pio, NULL, childvd,
109e716630dSMartin Matuska 	    VDEV_BOOT_OFFSET - VDEV_LABEL_START_SIZE, abd, size, ZIO_TYPE_READ,
110e716630dSMartin Matuska 	    ZIO_PRIORITY_ASYNC_READ, 0, vdev_child_done, pio));
111e716630dSMartin Matuska 	zio_wait(pio);
112e716630dSMartin Matuska 
113e716630dSMartin Matuska 	unsigned char *buf = abd_to_buf(abd);
114e716630dSMartin Matuska 
115e716630dSMartin Matuska 	/*
116e716630dSMartin Matuska 	 * The BTX server has a special header at the begining.
117e716630dSMartin Matuska 	 *
118e716630dSMartin Matuska 	 * btx_hdr:	.byte 0xeb		# Machine ID
119e716630dSMartin Matuska 	 *		.byte 0xe		# Header size
120e716630dSMartin Matuska 	 *		.ascii "BTX"		# Magic
121e716630dSMartin Matuska 	 *		.byte 0x1		# Major version
122e716630dSMartin Matuska 	 *		.byte 0x2		# Minor version
123e716630dSMartin Matuska 	 *		.byte BTX_FLAGS		# Flags
124e716630dSMartin Matuska 	 */
125e716630dSMartin Matuska 	if (buf[0] == 0xeb && buf[1] == 0x0e &&
126e716630dSMartin Matuska 	    buf[2] == 'B' && buf[3] == 'T' && buf[4] == 'X') {
127e716630dSMartin Matuska 		abd_free(abd);
128e716630dSMartin Matuska 		return (EBUSY);
129e716630dSMartin Matuska 	}
130e716630dSMartin Matuska 
131e716630dSMartin Matuska 	abd_free(abd);
132e716630dSMartin Matuska 	return (0);
133e716630dSMartin Matuska }
134