/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or https://opensource.org/licenses/CDDL-1.0. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 2018 Intel Corporation. * Copyright (c) 2020 by Lawrence Livermore National Security, LLC. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef ZFS_DEBUG #include /* For vdev_xlate() in vdev_draid_io_verify() */ #endif /* * dRAID is a distributed spare implementation for ZFS. A dRAID vdev is * comprised of multiple raidz redundancy groups which are spread over the * dRAID children. To ensure an even distribution, and avoid hot spots, a * permutation mapping is applied to the order of the dRAID children. * This mixing effectively distributes the parity columns evenly over all * of the disks in the dRAID. * * This is beneficial because it means when resilvering all of the disks * can participate thereby increasing the available IOPs and bandwidth. * Furthermore, by reserving a small fraction of each child's total capacity * virtual distributed spare disks can be created. These spares similarly * benefit from the performance gains of spanning all of the children. The * consequence of which is that resilvering to a distributed spare can * substantially reduce the time required to restore full parity to pool * with a failed disks. * * === dRAID group layout === * * First, let's define a "row" in the configuration to be a 16M chunk from * each physical drive at the same offset. This is the minimum allowable * size since it must be possible to store a full 16M block when there is * only a single data column. Next, we define a "group" to be a set of * sequential disks containing both the parity and data columns. We allow * groups to span multiple rows in order to align any group size to any * number of physical drives. Finally, a "slice" is comprised of the rows * which contain the target number of groups. The permutation mappings * are applied in a round robin fashion to each slice. * * Given D+P drives in a group (including parity drives) and C-S physical * drives (not including the spare drives), we can distribute the groups * across R rows without remainder by selecting the least common multiple * of D+P and C-S as the number of groups; i.e. ngroups = LCM(D+P, C-S). * * In the example below, there are C=14 physical drives in the configuration * with S=2 drives worth of spare capacity. Each group has a width of 9 * which includes D=8 data and P=1 parity drive. There are 4 groups and * 3 rows per slice. Each group has a size of 144M (16M * 9) and a slice * size is 576M (144M * 4). When allocating from a dRAID each group is * filled before moving on to the next as show in slice0 below. * * data disks (8 data + 1 parity) spares (2) * +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ * ^ | 2 | 6 | 1 | 11| 4 | 0 | 7 | 10| 8 | 9 | 13| 5 | 12| 3 | device map 0 * | +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ * | | group 0 | group 1..| | * | +-----------------------------------+-----------+-------| * | | 0 1 2 3 4 5 6 7 8 | 36 37 38| | r * | | 9 10 11 12 13 14 15 16 17| 45 46 47| | o * | | 18 19 20 21 22 23 24 25 26| 54 55 56| | w * | 27 28 29 30 31 32 33 34 35| 63 64 65| | 0 * s +-----------------------+-----------------------+-------+ * l | ..group 1 | group 2.. | | * i +-----------------------+-----------------------+-------+ * c | 39 40 41 42 43 44| 72 73 74 75 76 77| | r * e | 48 49 50 51 52 53| 81 82 83 84 85 86| | o * 0 | 57 58 59 60 61 62| 90 91 92 93 94 95| | w * | 66 67 68 69 70 71| 99 100 101 102 103 104| | 1 * | +-----------+-----------+-----------------------+-------+ * | |..group 2 | group 3 | | * | +-----------+-----------+-----------------------+-------+ * | | 78 79 80|108 109 110 111 112 113 114 115 116| | r * | | 87 88 89|117 118 119 120 121 122 123 124 125| | o * | | 96 97 98|126 127 128 129 130 131 132 133 134| | w * v |105 106 107|135 136 137 138 139 140 141 142 143| | 2 * +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ * | 9 | 11| 12| 2 | 4 | 1 | 3 | 0 | 10| 13| 8 | 5 | 6 | 7 | device map 1 * s +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ * l | group 4 | group 5..| | row 3 * i +-----------------------+-----------+-----------+-------| * c | ..group 5 | group 6.. | | row 4 * e +-----------+-----------+-----------------------+-------+ * 1 |..group 6 | group 7 | | row 5 * +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ * | 3 | 5 | 10| 8 | 6 | 11| 12| 0 | 2 | 4 | 7 | 1 | 9 | 13| device map 2 * s +===+===+===+===+===+===+===+===+===+===+===+===+===+===+ * l | group 8 | group 9..| | row 6 * i +-----------------------------------------------+-------| * c | ..group 9 | group 10.. | | row 7 * e +-----------------------+-----------------------+-------+ * 2 |..group 10 | group 11 | | row 8 * +-----------+-----------------------------------+-------+ * * This layout has several advantages over requiring that each row contain * a whole number of groups. * * 1. The group count is not a relevant parameter when defining a dRAID * layout. Only the group width is needed, and *all* groups will have * the desired size. * * 2. All possible group widths (<= physical disk count) can be supported. * * 3. The logic within vdev_draid.c is simplified when the group width is * the same for all groups (although some of the logic around computing * permutation numbers and drive offsets is more complicated). * * N.B. The following array describes all valid dRAID permutation maps. * Each row is used to generate a permutation map for a different number * of children from a unique seed. The seeds were generated and carefully * evaluated by the 'draid' utility in order to provide balanced mappings. * In addition to the seed a checksum of the in-memory mapping is stored * for verification. * * The imbalance ratio of a given failure (e.g. 5 disks wide, child 3 failed, * with a given permutation map) is the ratio of the amounts of I/O that will * be sent to the least and most busy disks when resilvering. The average * imbalance ratio (of a given number of disks and permutation map) is the * average of the ratios of all possible single and double disk failures. * * In order to achieve a low imbalance ratio the number of permutations in * the mapping must be significantly larger than the number of children. * For dRAID the number of permutations has been limited to 512 to minimize * the map size. This does result in a gradually increasing imbalance ratio * as seen in the table below. Increasing the number of permutations for * larger child counts would reduce the imbalance ratio. However, in practice * when there are a large number of children each child is responsible for * fewer total IOs so it's less of a concern. * * Note these values are hard coded and must never be changed. Existing * pools depend on the same mapping always being generated in order to * read and write from the correct locations. Any change would make * existing pools completely inaccessible. */ static const draid_map_t draid_maps[VDEV_DRAID_MAX_MAPS] = { { 2, 256, 0x89ef3dabbcc7de37, 0x00000000433d433d }, /* 1.000 */ { 3, 256, 0x89a57f3de98121b4, 0x00000000bcd8b7b5 }, /* 1.000 */ { 4, 256, 0xc9ea9ec82340c885, 0x00000001819d7c69 }, /* 1.000 */ { 5, 256, 0xf46733b7f4d47dfd, 0x00000002a1648d74 }, /* 1.010 */ { 6, 256, 0x88c3c62d8585b362, 0x00000003d3b0c2c4 }, /* 1.031 */ { 7, 256, 0x3a65d809b4d1b9d5, 0x000000055c4183ee }, /* 1.043 */ { 8, 256, 0xe98930e3c5d2e90a, 0x00000006edfb0329 }, /* 1.059 */ { 9, 256, 0x5a5430036b982ccb, 0x00000008ceaf6934 }, /* 1.056 */ { 10, 256, 0x92bf389e9eadac74, 0x0000000b26668c09 }, /* 1.072 */ { 11, 256, 0x74ccebf1dcf3ae80, 0x0000000dd691358c }, /* 1.083 */ { 12, 256, 0x8847e41a1a9f5671, 0x00000010a0c63c8e }, /* 1.097 */ { 13, 256, 0x7481b56debf0e637, 0x0000001424121fe4 }, /* 1.100 */ { 14, 256, 0x559b8c44065f8967, 0x00000016ab2ff079 }, /* 1.121 */ { 15, 256, 0x34c49545a2ee7f01, 0x0000001a6028efd6 }, /* 1.103 */ { 16, 256, 0xb85f4fa81a7698f7, 0x0000001e95ff5e66 }, /* 1.111 */ { 17, 256, 0x6353e47b7e47aba0, 0x00000021a81fa0fe }, /* 1.133 */ { 18, 256, 0xaa549746b1cbb81c, 0x00000026f02494c9 }, /* 1.131 */ { 19, 256, 0x892e343f2f31d690, 0x00000029eb392835 }, /* 1.130 */ { 20, 256, 0x76914824db98cc3f, 0x0000003004f31a7c }, /* 1.141 */ { 21, 256, 0x4b3cbabf9cfb1d0f, 0x00000036363a2408 }, /* 1.139 */ { 22, 256, 0xf45c77abb4f035d4, 0x00000038dd0f3e84 }, /* 1.150 */ { 23, 256, 0x5e18bd7f3fd4baf4, 0x0000003f0660391f }, /* 1.174 */ { 24, 256, 0xa7b3a4d285d6503b, 0x000000443dfc9ff6 }, /* 1.168 */ { 25, 256, 0x56ac7dd967521f5a, 0x0000004b03a87eb7 }, /* 1.180 */ { 26, 256, 0x3a42dfda4eb880f7, 0x000000522c719bba }, /* 1.226 */ { 27, 256, 0xd200d2fc6b54bf60, 0x0000005760b4fdf5 }, /* 1.228 */ { 28, 256, 0xc52605bbd486c546, 0x0000005e00d8f74c }, /* 1.217 */ { 29, 256, 0xc761779e63cd762f, 0x00000067be3cd85c }, /* 1.239 */ { 30, 256, 0xca577b1e07f85ca5, 0x0000006f5517f3e4 }, /* 1.238 */ { 31, 256, 0xfd50a593c518b3d4, 0x0000007370e7778f }, /* 1.273 */ { 32, 512, 0xc6c87ba5b042650b, 0x000000f7eb08a156 }, /* 1.191 */ { 33, 512, 0xc3880d0c9d458304, 0x0000010734b5d160 }, /* 1.199 */ { 34, 512, 0xe920927e4d8b2c97, 0x00000118c1edbce0 }, /* 1.195 */ { 35, 512, 0x8da7fcda87bde316, 0x0000012a3e9f9110 }, /* 1.201 */ { 36, 512, 0xcf09937491514a29, 0x0000013bd6a24bef }, /* 1.194 */ { 37, 512, 0x9b5abbf345cbd7cc, 0x0000014b9d90fac3 }, /* 1.237 */ { 38, 512, 0x506312a44668d6a9, 0x0000015e1b5f6148 }, /* 1.242 */ { 39, 512, 0x71659ede62b4755f, 0x00000173ef029bcd }, /* 1.231 */ { 40, 512, 0xa7fde73fb74cf2d7, 0x000001866fb72748 }, /* 1.233 */ { 41, 512, 0x19e8b461a1dea1d3, 0x000001a046f76b23 }, /* 1.271 */ { 42, 512, 0x031c9b868cc3e976, 0x000001afa64c49d3 }, /* 1.263 */ { 43, 512, 0xbaa5125faa781854, 0x000001c76789e278 }, /* 1.270 */ { 44, 512, 0x4ed55052550d721b, 0x000001d800ccd8eb }, /* 1.281 */ { 45, 512, 0x0fd63ddbdff90677, 0x000001f08ad59ed2 }, /* 1.282 */ { 46, 512, 0x36d66546de7fdd6f, 0x000002016f09574b }, /* 1.286 */ { 47, 512, 0x99f997e7eafb69d7, 0x0000021e42e47cb6 }, /* 1.329 */ { 48, 512, 0xbecd9c2571312c5d, 0x000002320fe2872b }, /* 1.286 */ { 49, 512, 0xd97371329e488a32, 0x0000024cd73f2ca7 }, /* 1.322 */ { 50, 512, 0x30e9b136670749ee, 0x000002681c83b0e0 }, /* 1.335 */ { 51, 512, 0x11ad6bc8f47aaeb4, 0x0000027e9261b5d5 }, /* 1.305 */ { 52, 512, 0x68e445300af432c1, 0x0000029aa0eb7dbf }, /* 1.330 */ { 53, 512, 0x910fb561657ea98c, 0x000002b3dca04853 }, /* 1.365 */ { 54, 512, 0xd619693d8ce5e7a5, 0x000002cc280e9c97 }, /* 1.334 */ { 55, 512, 0x24e281f564dbb60a, 0x000002e9fa842713 }, /* 1.364 */ { 56, 512, 0x947a7d3bdaab44c5, 0x000003046680f72e }, /* 1.374 */ { 57, 512, 0x2d44fec9c093e0de, 0x00000324198ba810 }, /* 1.363 */ { 58, 512, 0x87743c272d29bb4c, 0x0000033ec48c9ac9 }, /* 1.401 */ { 59, 512, 0x96aa3b6f67f5d923, 0x0000034faead902c }, /* 1.392 */ { 60, 512, 0x94a4f1faf520b0d3, 0x0000037d713ab005 }, /* 1.360 */ { 61, 512, 0xb13ed3a272f711a2, 0x00000397368f3cbd }, /* 1.396 */ { 62, 512, 0x3b1b11805fa4a64a, 0x000003b8a5e2840c }, /* 1.453 */ { 63, 512, 0x4c74caad9172ba71, 0x000003d4be280290 }, /* 1.437 */ { 64, 512, 0x035ff643923dd29e, 0x000003fad6c355e1 }, /* 1.402 */ { 65, 512, 0x768e9171b11abd3c, 0x0000040eb07fed20 }, /* 1.459 */ { 66, 512, 0x75880e6f78a13ddd, 0x000004433d6acf14 }, /* 1.423 */ { 67, 512, 0x910b9714f698a877, 0x00000451ea65d5db }, /* 1.447 */ { 68, 512, 0x87f5db6f9fdcf5c7, 0x000004732169e3f7 }, /* 1.450 */ { 69, 512, 0x836d4968fbaa3706, 0x000004954068a380 }, /* 1.455 */ { 70, 512, 0xc567d73a036421ab, 0x000004bd7cb7bd3d }, /* 1.463 */ { 71, 512, 0x619df40f240b8fed, 0x000004e376c2e972 }, /* 1.463 */ { 72, 512, 0x42763a680d5bed8e, 0x000005084275c680 }, /* 1.452 */ { 73, 512, 0x5866f064b3230431, 0x0000052906f2c9ab }, /* 1.498 */ { 74, 512, 0x9fa08548b1621a44, 0x0000054708019247 }, /* 1.526 */ { 75, 512, 0xb6053078ce0fc303, 0x00000572cc5c72b0 }, /* 1.491 */ { 76, 512, 0x4a7aad7bf3890923, 0x0000058e987bc8e9 }, /* 1.470 */ { 77, 512, 0xe165613fd75b5a53, 0x000005c20473a211 }, /* 1.527 */ { 78, 512, 0x3ff154ac878163a6, 0x000005d659194bf3 }, /* 1.509 */ { 79, 512, 0x24b93ade0aa8a532, 0x0000060a201c4f8e }, /* 1.569 */ { 80, 512, 0xc18e2d14cd9bb554, 0x0000062c55cfe48c }, /* 1.555 */ { 81, 512, 0x98cc78302feb58b6, 0x0000066656a07194 }, /* 1.509 */ { 82, 512, 0xc6c5fd5a2abc0543, 0x0000067cff94fbf8 }, /* 1.596 */ { 83, 512, 0xa7962f514acbba21, 0x000006ab7b5afa2e }, /* 1.568 */ { 84, 512, 0xba02545069ddc6dc, 0x000006d19861364f }, /* 1.541 */ { 85, 512, 0x447c73192c35073e, 0x000006fce315ce35 }, /* 1.623 */ { 86, 512, 0x48beef9e2d42b0c2, 0x00000720a8e38b6b }, /* 1.620 */ { 87, 512, 0x4874cf98541a35e0, 0x00000758382a2273 }, /* 1.597 */ { 88, 512, 0xad4cf8333a31127a, 0x00000781e1651b1b }, /* 1.575 */ { 89, 512, 0x47ae4859d57888c1, 0x000007b27edbe5bc }, /* 1.627 */ { 90, 512, 0x06f7723cfe5d1891, 0x000007dc2a96d8eb }, /* 1.596 */ { 91, 512, 0xd4e44218d660576d, 0x0000080ac46f02d5 }, /* 1.622 */ { 92, 512, 0x7066702b0d5be1f2, 0x00000832c96d154e }, /* 1.695 */ { 93, 512, 0x011209b4f9e11fb9, 0x0000085eefda104c }, /* 1.605 */ { 94, 512, 0x47ffba30a0b35708, 0x00000899badc32dc }, /* 1.625 */ { 95, 512, 0x1a95a6ac4538aaa8, 0x000008b6b69a42b2 }, /* 1.687 */ { 96, 512, 0xbda2b239bb2008eb, 0x000008f22d2de38a }, /* 1.621 */ { 97, 512, 0x7ffa0bea90355c6c, 0x0000092e5b23b816 }, /* 1.699 */ { 98, 512, 0x1d56ba34be426795, 0x0000094f482e5d1b }, /* 1.688 */ { 99, 512, 0x0aa89d45c502e93d, 0x00000977d94a98ce }, /* 1.642 */ { 100, 512, 0x54369449f6857774, 0x000009c06c9b34cc }, /* 1.683 */ { 101, 512, 0xf7d4dd8445b46765, 0x000009e5dc542259 }, /* 1.755 */ { 102, 512, 0xfa8866312f169469, 0x00000a16b54eae93 }, /* 1.692 */ { 103, 512, 0xd8a5aea08aef3ff9, 0x00000a381d2cbfe7 }, /* 1.747 */ { 104, 512, 0x66bcd2c3d5f9ef0e, 0x00000a8191817be7 }, /* 1.751 */ { 105, 512, 0x3fb13a47a012ec81, 0x00000ab562b9a254 }, /* 1.751 */ { 106, 512, 0x43100f01c9e5e3ca, 0x00000aeee84c185f }, /* 1.726 */ { 107, 512, 0xca09c50ccee2d054, 0x00000b1c359c047d }, /* 1.788 */ { 108, 512, 0xd7176732ac503f9b, 0x00000b578bc52a73 }, /* 1.740 */ { 109, 512, 0xed206e51f8d9422d, 0x00000b8083e0d960 }, /* 1.780 */ { 110, 512, 0x17ead5dc6ba0dcd6, 0x00000bcfb1a32ca8 }, /* 1.836 */ { 111, 512, 0x5f1dc21e38a969eb, 0x00000c0171becdd6 }, /* 1.778 */ { 112, 512, 0xddaa973de33ec528, 0x00000c3edaba4b95 }, /* 1.831 */ { 113, 512, 0x2a5eccd7735a3630, 0x00000c630664e7df }, /* 1.825 */ { 114, 512, 0xafcccee5c0b71446, 0x00000cb65392f6e4 }, /* 1.826 */ { 115, 512, 0x8fa30c5e7b147e27, 0x00000cd4db391e55 }, /* 1.843 */ { 116, 512, 0x5afe0711fdfafd82, 0x00000d08cb4ec35d }, /* 1.826 */ { 117, 512, 0x533a6090238afd4c, 0x00000d336f115d1b }, /* 1.803 */ { 118, 512, 0x90cf11b595e39a84, 0x00000d8e041c2048 }, /* 1.857 */ { 119, 512, 0x0d61a3b809444009, 0x00000dcb798afe35 }, /* 1.877 */ { 120, 512, 0x7f34da0f54b0d114, 0x00000df3922664e1 }, /* 1.849 */ { 121, 512, 0xa52258d5b72f6551, 0x00000e4d37a9872d }, /* 1.867 */ { 122, 512, 0xc1de54d7672878db, 0x00000e6583a94cf6 }, /* 1.978 */ { 123, 512, 0x1d03354316a414ab, 0x00000ebffc50308d }, /* 1.947 */ { 124, 512, 0xcebdcc377665412c, 0x00000edee1997cea }, /* 1.865 */ { 125, 512, 0x4ddd4c04b1a12344, 0x00000f21d64b373f }, /* 1.881 */ { 126, 512, 0x64fc8f94e3973658, 0x00000f8f87a8896b }, /* 1.882 */ { 127, 512, 0x68765f78034a334e, 0x00000fb8fe62197e }, /* 1.867 */ { 128, 512, 0xaf36b871a303e816, 0x00000fec6f3afb1e }, /* 1.972 */ { 129, 512, 0x2a4cbf73866c3a28, 0x00001027febfe4e5 }, /* 1.896 */ { 130, 512, 0x9cb128aacdcd3b2f, 0x0000106aa8ac569d }, /* 1.965 */ { 131, 512, 0x5511d41c55869124, 0x000010bbd755ddf1 }, /* 1.963 */ { 132, 512, 0x42f92461937f284a, 0x000010fb8bceb3b5 }, /* 1.925 */ { 133, 512, 0xe2d89a1cf6f1f287, 0x0000114cf5331e34 }, /* 1.862 */ { 134, 512, 0xdc631a038956200e, 0x0000116428d2adc5 }, /* 2.042 */ { 135, 512, 0xb2e5ac222cd236be, 0x000011ca88e4d4d2 }, /* 1.935 */ { 136, 512, 0xbc7d8236655d88e7, 0x000011e39cb94e66 }, /* 2.005 */ { 137, 512, 0x073e02d88d2d8e75, 0x0000123136c7933c }, /* 2.041 */ { 138, 512, 0x3ddb9c3873166be0, 0x00001280e4ec6d52 }, /* 1.997 */ { 139, 512, 0x7d3b1a845420e1b5, 0x000012c2e7cd6a44 }, /* 1.996 */ { 140, 512, 0x60102308aa7b2a6c, 0x000012fc490e6c7d }, /* 2.053 */ { 141, 512, 0xdb22bb2f9eb894aa, 0x00001343f5a85a1a }, /* 1.971 */ { 142, 512, 0xd853f879a13b1606, 0x000013bb7d5f9048 }, /* 2.018 */ { 143, 512, 0x001620a03f804b1d, 0x000013e74cc794fd }, /* 1.961 */ { 144, 512, 0xfdb52dda76fbf667, 0x00001442d2f22480 }, /* 2.046 */ { 145, 512, 0xa9160110f66e24ff, 0x0000144b899f9dbb }, /* 1.968 */ { 146, 512, 0x77306a30379ae03b, 0x000014cb98eb1f81 }, /* 2.143 */ { 147, 512, 0x14f5985d2752319d, 0x000014feab821fc9 }, /* 2.064 */ { 148, 512, 0xa4b8ff11de7863f8, 0x0000154a0e60b9c9 }, /* 2.023 */ { 149, 512, 0x44b345426455c1b3, 0x000015999c3c569c }, /* 2.136 */ { 150, 512, 0x272677826049b46c, 0x000015c9697f4b92 }, /* 2.063 */ { 151, 512, 0x2f9216e2cd74fe40, 0x0000162b1f7bbd39 }, /* 1.974 */ { 152, 512, 0x706ae3e763ad8771, 0x00001661371c55e1 }, /* 2.210 */ { 153, 512, 0xf7fd345307c2480e, 0x000016e251f28b6a }, /* 2.006 */ { 154, 512, 0x6e94e3d26b3139eb, 0x000016f2429bb8c6 }, /* 2.193 */ { 155, 512, 0x5458bbfbb781fcba, 0x0000173efdeca1b9 }, /* 2.163 */ { 156, 512, 0xa80e2afeccd93b33, 0x000017bfdcb78adc }, /* 2.046 */ { 157, 512, 0x1e4ccbb22796cf9d, 0x00001826fdcc39c9 }, /* 2.084 */ { 158, 512, 0x8fba4b676aaa3663, 0x00001841a1379480 }, /* 2.264 */ { 159, 512, 0xf82b843814b315fa, 0x000018886e19b8a3 }, /* 2.074 */ { 160, 512, 0x7f21e920ecf753a3, 0x0000191812ca0ea7 }, /* 2.282 */ { 161, 512, 0x48bb8ea2c4caa620, 0x0000192f310faccf }, /* 2.148 */ { 162, 512, 0x5cdb652b4952c91b, 0x0000199e1d7437c7 }, /* 2.355 */ { 163, 512, 0x6ac1ba6f78c06cd4, 0x000019cd11f82c70 }, /* 2.164 */ { 164, 512, 0x9faf5f9ca2669a56, 0x00001a18d5431f6a }, /* 2.393 */ { 165, 512, 0xaa57e9383eb01194, 0x00001a9e7d253d85 }, /* 2.178 */ { 166, 512, 0x896967bf495c34d2, 0x00001afb8319b9fc }, /* 2.334 */ { 167, 512, 0xdfad5f05de225f1b, 0x00001b3a59c3093b }, /* 2.266 */ { 168, 512, 0xfd299a99f9f2abdd, 0x00001bb6f1a10799 }, /* 2.304 */ { 169, 512, 0xdda239e798fe9fd4, 0x00001bfae0c9692d }, /* 2.218 */ { 170, 512, 0x5fca670414a32c3e, 0x00001c22129dbcff }, /* 2.377 */ { 171, 512, 0x1bb8934314b087de, 0x00001c955db36cd0 }, /* 2.155 */ { 172, 512, 0xd96394b4b082200d, 0x00001cfc8619b7e6 }, /* 2.404 */ { 173, 512, 0xb612a7735b1c8cbc, 0x00001d303acdd585 }, /* 2.205 */ { 174, 512, 0x28e7430fe5875fe1, 0x00001d7ed5b3697d }, /* 2.359 */ { 175, 512, 0x5038e89efdd981b9, 0x00001dc40ec35c59 }, /* 2.158 */ { 176, 512, 0x075fd78f1d14db7c, 0x00001e31c83b4a2b }, /* 2.614 */ { 177, 512, 0xc50fafdb5021be15, 0x00001e7cdac82fbc }, /* 2.239 */ { 178, 512, 0xe6dc7572ce7b91c7, 0x00001edd8bb454fc }, /* 2.493 */ { 179, 512, 0x21f7843e7beda537, 0x00001f3a8e019d6c }, /* 2.327 */ { 180, 512, 0xc83385e20b43ec82, 0x00001f70735ec137 }, /* 2.231 */ { 181, 512, 0xca818217dddb21fd, 0x0000201ca44c5a3c }, /* 2.237 */ { 182, 512, 0xe6035defea48f933, 0x00002038e3346658 }, /* 2.691 */ { 183, 512, 0x47262a4f953dac5a, 0x000020c2e554314e }, /* 2.170 */ { 184, 512, 0xe24c7246260873ea, 0x000021197e618d64 }, /* 2.600 */ { 185, 512, 0xeef6b57c9b58e9e1, 0x0000217ea48ecddc }, /* 2.391 */ { 186, 512, 0x2becd3346e386142, 0x000021c496d4a5f9 }, /* 2.677 */ { 187, 512, 0x63c6207bdf3b40a3, 0x0000220e0f2eec0c }, /* 2.410 */ { 188, 512, 0x3056ce8989767d4b, 0x0000228eb76cd137 }, /* 2.776 */ { 189, 512, 0x91af61c307cee780, 0x000022e17e2ea501 }, /* 2.266 */ { 190, 512, 0xda359da225f6d54f, 0x00002358a2debc19 }, /* 2.717 */ { 191, 512, 0x0a5f7a2a55607ba0, 0x0000238a79dac18c }, /* 2.474 */ { 192, 512, 0x27bb75bf5224638a, 0x00002403a58e2351 }, /* 2.673 */ { 193, 512, 0x1ebfdb94630f5d0f, 0x00002492a10cb339 }, /* 2.420 */ { 194, 512, 0x6eae5e51d9c5f6fb, 0x000024ce4bf98715 }, /* 2.898 */ { 195, 512, 0x08d903b4daedc2e0, 0x0000250d1e15886c }, /* 2.363 */ { 196, 512, 0xc722a2f7fa7cd686, 0x0000258a99ed0c9e }, /* 2.747 */ { 197, 512, 0x8f71faf0e54e361d, 0x000025dee11976f5 }, /* 2.531 */ { 198, 512, 0x87f64695c91a54e7, 0x0000264e00a43da0 }, /* 2.707 */ { 199, 512, 0xc719cbac2c336b92, 0x000026d327277ac1 }, /* 2.315 */ { 200, 512, 0xe7e647afaf771ade, 0x000027523a5c44bf }, /* 3.012 */ { 201, 512, 0x12d4b5c38ce8c946, 0x0000273898432545 }, /* 2.378 */ { 202, 512, 0xf2e0cd4067bdc94a, 0x000027e47bb2c935 }, /* 2.969 */ { 203, 512, 0x21b79f14d6d947d3, 0x0000281e64977f0d }, /* 2.594 */ { 204, 512, 0x515093f952f18cd6, 0x0000289691a473fd }, /* 2.763 */ { 205, 512, 0xd47b160a1b1022c8, 0x00002903e8b52411 }, /* 2.457 */ { 206, 512, 0xc02fc96684715a16, 0x0000297515608601 }, /* 3.057 */ { 207, 512, 0xef51e68efba72ed0, 0x000029ef73604804 }, /* 2.590 */ { 208, 512, 0x9e3be6e5448b4f33, 0x00002a2846ed074b }, /* 3.047 */ { 209, 512, 0x81d446c6d5fec063, 0x00002a92ca693455 }, /* 2.676 */ { 210, 512, 0xff215de8224e57d5, 0x00002b2271fe3729 }, /* 2.993 */ { 211, 512, 0xe2524d9ba8f69796, 0x00002b64b99c3ba2 }, /* 2.457 */ { 212, 512, 0xf6b28e26097b7e4b, 0x00002bd768b6e068 }, /* 3.182 */ { 213, 512, 0x893a487f30ce1644, 0x00002c67f722b4b2 }, /* 2.563 */ { 214, 512, 0x386566c3fc9871df, 0x00002cc1cf8b4037 }, /* 3.025 */ { 215, 512, 0x1e0ed78edf1f558a, 0x00002d3948d36c7f }, /* 2.730 */ { 216, 512, 0xe3bc20c31e61f113, 0x00002d6d6b12e025 }, /* 3.036 */ { 217, 512, 0xd6c3ad2e23021882, 0x00002deff7572241 }, /* 2.722 */ { 218, 512, 0xb4a9f95cf0f69c5a, 0x00002e67d537aa36 }, /* 3.356 */ { 219, 512, 0x6e98ed6f6c38e82f, 0x00002e9720626789 }, /* 2.697 */ { 220, 512, 0x2e01edba33fddac7, 0x00002f407c6b0198 }, /* 2.979 */ { 221, 512, 0x559d02e1f5f57ccc, 0x00002fb6a5ab4f24 }, /* 2.858 */ { 222, 512, 0xac18f5a916adcd8e, 0x0000304ae1c5c57e }, /* 3.258 */ { 223, 512, 0x15789fbaddb86f4b, 0x0000306f6e019c78 }, /* 2.693 */ { 224, 512, 0xf4a9c36d5bc4c408, 0x000030da40434213 }, /* 3.259 */ { 225, 512, 0xf640f90fd2727f44, 0x00003189ed37b90c }, /* 2.733 */ { 226, 512, 0xb5313d390d61884a, 0x000031e152616b37 }, /* 3.235 */ { 227, 512, 0x4bae6b3ce9160939, 0x0000321f40aeac42 }, /* 2.983 */ { 228, 512, 0x838c34480f1a66a1, 0x000032f389c0f78e }, /* 3.308 */ { 229, 512, 0xb1c4a52c8e3d6060, 0x0000330062a40284 }, /* 2.715 */ { 230, 512, 0xe0f1110c6d0ed822, 0x0000338be435644f }, /* 3.540 */ { 231, 512, 0x9f1a8ccdcea68d4b, 0x000034045a4e97e1 }, /* 2.779 */ { 232, 512, 0x3261ed62223f3099, 0x000034702cfc401c }, /* 3.084 */ { 233, 512, 0xf2191e2311022d65, 0x00003509dd19c9fc }, /* 2.987 */ { 234, 512, 0xf102a395c2033abc, 0x000035654dc96fae }, /* 3.341 */ { 235, 512, 0x11fe378f027906b6, 0x000035b5193b0264 }, /* 2.793 */ { 236, 512, 0xf777f2c026b337aa, 0x000036704f5d9297 }, /* 3.518 */ { 237, 512, 0x1b04e9c2ee143f32, 0x000036dfbb7af218 }, /* 2.962 */ { 238, 512, 0x2fcec95266f9352c, 0x00003785c8df24a9 }, /* 3.196 */ { 239, 512, 0xfe2b0e47e427dd85, 0x000037cbdf5da729 }, /* 2.914 */ { 240, 512, 0x72b49bf2225f6c6d, 0x0000382227c15855 }, /* 3.408 */ { 241, 512, 0x50486b43df7df9c7, 0x0000389b88be6453 }, /* 2.903 */ { 242, 512, 0x5192a3e53181c8ab, 0x000038ddf3d67263 }, /* 3.778 */ { 243, 512, 0xe9f5d8365296fd5e, 0x0000399f1c6c9e9c }, /* 3.026 */ { 244, 512, 0xc740263f0301efa8, 0x00003a147146512d }, /* 3.347 */ { 245, 512, 0x23cd0f2b5671e67d, 0x00003ab10bcc0d9d }, /* 3.212 */ { 246, 512, 0x002ccc7e5cd41390, 0x00003ad6cd14a6c0 }, /* 3.482 */ { 247, 512, 0x9aafb3c02544b31b, 0x00003b8cb8779fb0 }, /* 3.146 */ { 248, 512, 0x72ba07a78b121999, 0x00003c24142a5a3f }, /* 3.626 */ { 249, 512, 0x3d784aa58edfc7b4, 0x00003cd084817d99 }, /* 2.952 */ { 250, 512, 0xaab750424d8004af, 0x00003d506a8e098e }, /* 3.463 */ { 251, 512, 0x84403fcf8e6b5ca2, 0x00003d4c54c2aec4 }, /* 3.131 */ { 252, 512, 0x71eb7455ec98e207, 0x00003e655715cf2c }, /* 3.538 */ { 253, 512, 0xd752b4f19301595b, 0x00003ecd7b2ca5ac }, /* 2.974 */ { 254, 512, 0xc4674129750499de, 0x00003e99e86d3e95 }, /* 3.843 */ { 255, 512, 0x9772baff5cd12ef5, 0x00003f895c019841 }, /* 3.088 */ }; /* * Verify the map is valid. Each device index must appear exactly * once in every row, and the permutation array checksum must match. */ static int verify_perms(uint8_t *perms, uint64_t children, uint64_t nperms, uint64_t checksum) { int countssz = sizeof (uint16_t) * children; uint16_t *counts = kmem_zalloc(countssz, KM_SLEEP); for (int i = 0; i < nperms; i++) { for (int j = 0; j < children; j++) { uint8_t val = perms[(i * children) + j]; if (val >= children || counts[val] != i) { kmem_free(counts, countssz); return (EINVAL); } counts[val]++; } } if (checksum != 0) { int permssz = sizeof (uint8_t) * children * nperms; zio_cksum_t cksum; fletcher_4_native_varsize(perms, permssz, &cksum); if (checksum != cksum.zc_word[0]) { kmem_free(counts, countssz); return (ECKSUM); } } kmem_free(counts, countssz); return (0); } /* * Generate the permutation array for the draid_map_t. These maps control * the placement of all data in a dRAID. Therefore it's critical that the * seed always generates the same mapping. We provide our own pseudo-random * number generator for this purpose. */ int vdev_draid_generate_perms(const draid_map_t *map, uint8_t **permsp) { VERIFY3U(map->dm_children, >=, VDEV_DRAID_MIN_CHILDREN); VERIFY3U(map->dm_children, <=, VDEV_DRAID_MAX_CHILDREN); VERIFY3U(map->dm_seed, !=, 0); VERIFY3U(map->dm_nperms, !=, 0); VERIFY3P(map->dm_perms, ==, NULL); #ifdef _KERNEL /* * The kernel code always provides both a map_seed and checksum. * Only the tests/zfs-tests/cmd/draid/draid.c utility will provide * a zero checksum when generating new candidate maps. */ VERIFY3U(map->dm_checksum, !=, 0); #endif uint64_t children = map->dm_children; uint64_t nperms = map->dm_nperms; int rowsz = sizeof (uint8_t) * children; int permssz = rowsz * nperms; uint8_t *perms; /* Allocate the permutation array */ perms = vmem_alloc(permssz, KM_SLEEP); /* Setup an initial row with a known pattern */ uint8_t *initial_row = kmem_alloc(rowsz, KM_SLEEP); for (int i = 0; i < children; i++) initial_row[i] = i; uint64_t draid_seed[2] = { VDEV_DRAID_SEED, map->dm_seed }; uint8_t *current_row, *previous_row = initial_row; /* * Perform a Fisher-Yates shuffle of each row using the previous * row as the starting point. An initial_row with known pattern * is used as the input for the first row. */ for (int i = 0; i < nperms; i++) { current_row = &perms[i * children]; memcpy(current_row, previous_row, rowsz); for (int j = children - 1; j > 0; j--) { uint64_t k = vdev_draid_rand(draid_seed) % (j + 1); uint8_t val = current_row[j]; current_row[j] = current_row[k]; current_row[k] = val; } previous_row = current_row; } kmem_free(initial_row, rowsz); int error = verify_perms(perms, children, nperms, map->dm_checksum); if (error) { vmem_free(perms, permssz); return (error); } *permsp = perms; return (0); } /* * Lookup the fixed draid_map_t for the requested number of children. */ int vdev_draid_lookup_map(uint64_t children, const draid_map_t **mapp) { for (int i = 0; i < VDEV_DRAID_MAX_MAPS; i++) { if (draid_maps[i].dm_children == children) { *mapp = &draid_maps[i]; return (0); } } return (ENOENT); } /* * Lookup the permutation array and iteration id for the provided offset. */ static void vdev_draid_get_perm(vdev_draid_config_t *vdc, uint64_t pindex, uint8_t **base, uint64_t *iter) { uint64_t ncols = vdc->vdc_children; uint64_t poff = pindex % (vdc->vdc_nperms * ncols); *base = vdc->vdc_perms + (poff / ncols) * ncols; *iter = poff % ncols; } static inline uint64_t vdev_draid_permute_id(vdev_draid_config_t *vdc, uint8_t *base, uint64_t iter, uint64_t index) { return ((base[index] + iter) % vdc->vdc_children); } /* * Return the asize which is the psize rounded up to a full group width. * i.e. vdev_draid_psize_to_asize(). */ static uint64_t vdev_draid_asize(vdev_t *vd, uint64_t psize) { vdev_draid_config_t *vdc = vd->vdev_tsd; uint64_t ashift = vd->vdev_ashift; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); uint64_t rows = ((psize - 1) / (vdc->vdc_ndata << ashift)) + 1; uint64_t asize = (rows * vdc->vdc_groupwidth) << ashift; ASSERT3U(asize, !=, 0); ASSERT3U(asize % (vdc->vdc_groupwidth), ==, 0); return (asize); } /* * Deflate the asize to the psize, this includes stripping parity. */ uint64_t vdev_draid_asize_to_psize(vdev_t *vd, uint64_t asize) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT0(asize % vdc->vdc_groupwidth); return ((asize / vdc->vdc_groupwidth) * vdc->vdc_ndata); } /* * Convert a logical offset to the corresponding group number. */ static uint64_t vdev_draid_offset_to_group(vdev_t *vd, uint64_t offset) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); return (offset / vdc->vdc_groupsz); } /* * Convert a group number to the logical starting offset for that group. */ static uint64_t vdev_draid_group_to_offset(vdev_t *vd, uint64_t group) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); return (group * vdc->vdc_groupsz); } /* * Full stripe writes. When writing, all columns (D+P) are required. Parity * is calculated over all the columns, including empty zero filled sectors, * and each is written to disk. While only the data columns are needed for * a normal read, all of the columns are required for reconstruction when * performing a sequential resilver. * * For "big columns" it's sufficient to map the correct range of the zio ABD. * Partial columns require allocating a gang ABD in order to zero fill the * empty sectors. When the column is empty a zero filled sector must be * mapped. In all cases the data ABDs must be the same size as the parity * ABDs (e.g. rc->rc_size == parity_size). */ static void vdev_draid_map_alloc_write(zio_t *zio, uint64_t abd_offset, raidz_row_t *rr) { uint64_t skip_size = 1ULL << zio->io_vd->vdev_top->vdev_ashift; uint64_t parity_size = rr->rr_col[0].rc_size; uint64_t abd_off = abd_offset; ASSERT3U(zio->io_type, ==, ZIO_TYPE_WRITE); ASSERT3U(parity_size, ==, abd_get_size(rr->rr_col[0].rc_abd)); for (uint64_t c = rr->rr_firstdatacol; c < rr->rr_cols; c++) { raidz_col_t *rc = &rr->rr_col[c]; if (rc->rc_size == 0) { /* empty data column (small write), add a skip sector */ ASSERT3U(skip_size, ==, parity_size); rc->rc_abd = abd_get_zeros(skip_size); } else if (rc->rc_size == parity_size) { /* this is a "big column" */ rc->rc_abd = abd_get_offset_struct(&rc->rc_abdstruct, zio->io_abd, abd_off, rc->rc_size); } else { /* short data column, add a skip sector */ ASSERT3U(rc->rc_size + skip_size, ==, parity_size); rc->rc_abd = abd_alloc_gang(); abd_gang_add(rc->rc_abd, abd_get_offset_size( zio->io_abd, abd_off, rc->rc_size), B_TRUE); abd_gang_add(rc->rc_abd, abd_get_zeros(skip_size), B_TRUE); } ASSERT3U(abd_get_size(rc->rc_abd), ==, parity_size); abd_off += rc->rc_size; rc->rc_size = parity_size; } IMPLY(abd_offset != 0, abd_off == zio->io_size); } /* * Scrub/resilver reads. In order to store the contents of the skip sectors * an additional ABD is allocated. The columns are handled in the same way * as a full stripe write except instead of using the zero ABD the newly * allocated skip ABD is used to back the skip sectors. In all cases the * data ABD must be the same size as the parity ABDs. */ static void vdev_draid_map_alloc_scrub(zio_t *zio, uint64_t abd_offset, raidz_row_t *rr) { uint64_t skip_size = 1ULL << zio->io_vd->vdev_top->vdev_ashift; uint64_t parity_size = rr->rr_col[0].rc_size; uint64_t abd_off = abd_offset; uint64_t skip_off = 0; ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); ASSERT3P(rr->rr_abd_empty, ==, NULL); if (rr->rr_nempty > 0) { rr->rr_abd_empty = abd_alloc_linear(rr->rr_nempty * skip_size, B_FALSE); } for (uint64_t c = rr->rr_firstdatacol; c < rr->rr_cols; c++) { raidz_col_t *rc = &rr->rr_col[c]; if (rc->rc_size == 0) { /* empty data column (small read), add a skip sector */ ASSERT3U(skip_size, ==, parity_size); ASSERT3U(rr->rr_nempty, !=, 0); rc->rc_abd = abd_get_offset_size(rr->rr_abd_empty, skip_off, skip_size); skip_off += skip_size; } else if (rc->rc_size == parity_size) { /* this is a "big column" */ rc->rc_abd = abd_get_offset_struct(&rc->rc_abdstruct, zio->io_abd, abd_off, rc->rc_size); } else { /* short data column, add a skip sector */ ASSERT3U(rc->rc_size + skip_size, ==, parity_size); ASSERT3U(rr->rr_nempty, !=, 0); rc->rc_abd = abd_alloc_gang(); abd_gang_add(rc->rc_abd, abd_get_offset_size( zio->io_abd, abd_off, rc->rc_size), B_TRUE); abd_gang_add(rc->rc_abd, abd_get_offset_size( rr->rr_abd_empty, skip_off, skip_size), B_TRUE); skip_off += skip_size; } uint64_t abd_size = abd_get_size(rc->rc_abd); ASSERT3U(abd_size, ==, abd_get_size(rr->rr_col[0].rc_abd)); /* * Increase rc_size so the skip ABD is included in subsequent * parity calculations. */ abd_off += rc->rc_size; rc->rc_size = abd_size; } IMPLY(abd_offset != 0, abd_off == zio->io_size); ASSERT3U(skip_off, ==, rr->rr_nempty * skip_size); } /* * Normal reads. In this common case only the columns containing data * are read in to the zio ABDs. Neither the parity columns or empty skip * sectors are read unless the checksum fails verification. In which case * vdev_raidz_read_all() will call vdev_draid_map_alloc_empty() to expand * the raid map in order to allow reconstruction using the parity data and * skip sectors. */ static void vdev_draid_map_alloc_read(zio_t *zio, uint64_t abd_offset, raidz_row_t *rr) { uint64_t abd_off = abd_offset; ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); for (uint64_t c = rr->rr_firstdatacol; c < rr->rr_cols; c++) { raidz_col_t *rc = &rr->rr_col[c]; if (rc->rc_size > 0) { rc->rc_abd = abd_get_offset_struct(&rc->rc_abdstruct, zio->io_abd, abd_off, rc->rc_size); abd_off += rc->rc_size; } } IMPLY(abd_offset != 0, abd_off == zio->io_size); } /* * Converts a normal "read" raidz_row_t to a "scrub" raidz_row_t. The key * difference is that an ABD is allocated to back skip sectors so they may * be read in to memory, verified, and repaired if needed. */ void vdev_draid_map_alloc_empty(zio_t *zio, raidz_row_t *rr) { uint64_t skip_size = 1ULL << zio->io_vd->vdev_top->vdev_ashift; uint64_t parity_size = rr->rr_col[0].rc_size; uint64_t skip_off = 0; ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); ASSERT3P(rr->rr_abd_empty, ==, NULL); if (rr->rr_nempty > 0) { rr->rr_abd_empty = abd_alloc_linear(rr->rr_nempty * skip_size, B_FALSE); } for (uint64_t c = rr->rr_firstdatacol; c < rr->rr_cols; c++) { raidz_col_t *rc = &rr->rr_col[c]; if (rc->rc_size == 0) { /* empty data column (small read), add a skip sector */ ASSERT3U(skip_size, ==, parity_size); ASSERT3U(rr->rr_nempty, !=, 0); ASSERT3P(rc->rc_abd, ==, NULL); rc->rc_abd = abd_get_offset_size(rr->rr_abd_empty, skip_off, skip_size); skip_off += skip_size; } else if (rc->rc_size == parity_size) { /* this is a "big column", nothing to add */ ASSERT3P(rc->rc_abd, !=, NULL); } else { /* * short data column, add a skip sector and clear * rc_tried to force the entire column to be re-read * thereby including the missing skip sector data * which is needed for reconstruction. */ ASSERT3U(rc->rc_size + skip_size, ==, parity_size); ASSERT3U(rr->rr_nempty, !=, 0); ASSERT3P(rc->rc_abd, !=, NULL); ASSERT(!abd_is_gang(rc->rc_abd)); abd_t *read_abd = rc->rc_abd; rc->rc_abd = abd_alloc_gang(); abd_gang_add(rc->rc_abd, read_abd, B_TRUE); abd_gang_add(rc->rc_abd, abd_get_offset_size( rr->rr_abd_empty, skip_off, skip_size), B_TRUE); skip_off += skip_size; rc->rc_tried = 0; } /* * Increase rc_size so the empty ABD is included in subsequent * parity calculations. */ rc->rc_size = parity_size; } ASSERT3U(skip_off, ==, rr->rr_nempty * skip_size); } /* * Verify that all empty sectors are zero filled before using them to * calculate parity. Otherwise, silent corruption in an empty sector will * result in bad parity being generated. That bad parity will then be * considered authoritative and overwrite the good parity on disk. This * is possible because the checksum is only calculated over the data, * thus it cannot be used to detect damage in empty sectors. */ int vdev_draid_map_verify_empty(zio_t *zio, raidz_row_t *rr) { uint64_t skip_size = 1ULL << zio->io_vd->vdev_top->vdev_ashift; uint64_t parity_size = rr->rr_col[0].rc_size; uint64_t skip_off = parity_size - skip_size; uint64_t empty_off = 0; int ret = 0; ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); ASSERT3P(rr->rr_abd_empty, !=, NULL); ASSERT3U(rr->rr_bigcols, >, 0); void *zero_buf = kmem_zalloc(skip_size, KM_SLEEP); for (int c = rr->rr_bigcols; c < rr->rr_cols; c++) { raidz_col_t *rc = &rr->rr_col[c]; ASSERT3P(rc->rc_abd, !=, NULL); ASSERT3U(rc->rc_size, ==, parity_size); if (abd_cmp_buf_off(rc->rc_abd, zero_buf, skip_off, skip_size) != 0) { vdev_raidz_checksum_error(zio, rc, rc->rc_abd); abd_zero_off(rc->rc_abd, skip_off, skip_size); rc->rc_error = SET_ERROR(ECKSUM); ret++; } empty_off += skip_size; } ASSERT3U(empty_off, ==, abd_get_size(rr->rr_abd_empty)); kmem_free(zero_buf, skip_size); return (ret); } /* * Given a logical address within a dRAID configuration, return the physical * address on the first drive in the group that this address maps to * (at position 'start' in permutation number 'perm'). */ static uint64_t vdev_draid_logical_to_physical(vdev_t *vd, uint64_t logical_offset, uint64_t *perm, uint64_t *start) { vdev_draid_config_t *vdc = vd->vdev_tsd; /* b is the dRAID (parent) sector offset. */ uint64_t ashift = vd->vdev_top->vdev_ashift; uint64_t b_offset = logical_offset >> ashift; /* * The height of a row in units of the vdev's minimum sector size. * This is the amount of data written to each disk of each group * in a given permutation. */ uint64_t rowheight_sectors = VDEV_DRAID_ROWHEIGHT >> ashift; /* * We cycle through a disk permutation every groupsz * ngroups chunk * of address space. Note that ngroups * groupsz must be a multiple * of the number of data drives (ndisks) in order to guarantee * alignment. So, for example, if our row height is 16MB, our group * size is 10, and there are 13 data drives in the draid, then ngroups * will be 13, we will change permutation every 2.08GB and each * disk will have 160MB of data per chunk. */ uint64_t groupwidth = vdc->vdc_groupwidth; uint64_t ngroups = vdc->vdc_ngroups; uint64_t ndisks = vdc->vdc_ndisks; /* * groupstart is where the group this IO will land in "starts" in * the permutation array. */ uint64_t group = logical_offset / vdc->vdc_groupsz; uint64_t groupstart = (group * groupwidth) % ndisks; ASSERT3U(groupstart + groupwidth, <=, ndisks + groupstart); *start = groupstart; /* b_offset is the sector offset within a group chunk */ b_offset = b_offset % (rowheight_sectors * groupwidth); ASSERT0(b_offset % groupwidth); /* * Find the starting byte offset on each child vdev: * - within a permutation there are ngroups groups spread over the * rows, where each row covers a slice portion of the disk * - each permutation has (groupwidth * ngroups) / ndisks rows * - so each permutation covers rows * slice portion of the disk * - so we need to find the row where this IO group target begins */ *perm = group / ngroups; uint64_t row = (*perm * ((groupwidth * ngroups) / ndisks)) + (((group % ngroups) * groupwidth) / ndisks); return (((rowheight_sectors * row) + (b_offset / groupwidth)) << ashift); } static uint64_t vdev_draid_map_alloc_row(zio_t *zio, raidz_row_t **rrp, uint64_t io_offset, uint64_t abd_offset, uint64_t abd_size) { vdev_t *vd = zio->io_vd; vdev_draid_config_t *vdc = vd->vdev_tsd; uint64_t ashift = vd->vdev_top->vdev_ashift; uint64_t io_size = abd_size; uint64_t io_asize = vdev_draid_asize(vd, io_size); uint64_t group = vdev_draid_offset_to_group(vd, io_offset); uint64_t start_offset = vdev_draid_group_to_offset(vd, group + 1); /* * Limit the io_size to the space remaining in the group. A second * row in the raidz_map_t is created for the remainder. */ if (io_offset + io_asize > start_offset) { io_size = vdev_draid_asize_to_psize(vd, start_offset - io_offset); } /* * At most a block may span the logical end of one group and the start * of the next group. Therefore, at the end of a group the io_size must * span the group width evenly and the remainder must be aligned to the * start of the next group. */ IMPLY(abd_offset == 0 && io_size < zio->io_size, (io_asize >> ashift) % vdc->vdc_groupwidth == 0); IMPLY(abd_offset != 0, vdev_draid_group_to_offset(vd, group) == io_offset); /* Lookup starting byte offset on each child vdev */ uint64_t groupstart, perm; uint64_t physical_offset = vdev_draid_logical_to_physical(vd, io_offset, &perm, &groupstart); /* * If there is less than groupwidth drives available after the group * start, the group is going to wrap onto the next row. 'wrap' is the * group disk number that starts on the next row. */ uint64_t ndisks = vdc->vdc_ndisks; uint64_t groupwidth = vdc->vdc_groupwidth; uint64_t wrap = groupwidth; if (groupstart + groupwidth > ndisks) wrap = ndisks - groupstart; /* The io size in units of the vdev's minimum sector size. */ const uint64_t psize = io_size >> ashift; /* * "Quotient": The number of data sectors for this stripe on all but * the "big column" child vdevs that also contain "remainder" data. */ uint64_t q = psize / vdc->vdc_ndata; /* * "Remainder": The number of partial stripe data sectors in this I/O. * This will add a sector to some, but not all, child vdevs. */ uint64_t r = psize - q * vdc->vdc_ndata; /* The number of "big columns" - those which contain remainder data. */ uint64_t bc = (r == 0 ? 0 : r + vdc->vdc_nparity); ASSERT3U(bc, <, groupwidth); /* The total number of data and parity sectors for this I/O. */ uint64_t tot = psize + (vdc->vdc_nparity * (q + (r == 0 ? 0 : 1))); ASSERT3U(vdc->vdc_nparity, >, 0); raidz_row_t *rr; rr = kmem_alloc(offsetof(raidz_row_t, rr_col[groupwidth]), KM_SLEEP); rr->rr_cols = groupwidth; rr->rr_scols = groupwidth; rr->rr_bigcols = bc; rr->rr_missingdata = 0; rr->rr_missingparity = 0; rr->rr_firstdatacol = vdc->vdc_nparity; rr->rr_abd_empty = NULL; #ifdef ZFS_DEBUG rr->rr_offset = io_offset; rr->rr_size = io_size; #endif *rrp = rr; uint8_t *base; uint64_t iter, asize = 0; vdev_draid_get_perm(vdc, perm, &base, &iter); for (uint64_t i = 0; i < groupwidth; i++) { raidz_col_t *rc = &rr->rr_col[i]; uint64_t c = (groupstart + i) % ndisks; /* increment the offset if we wrap to the next row */ if (i == wrap) physical_offset += VDEV_DRAID_ROWHEIGHT; rc->rc_devidx = vdev_draid_permute_id(vdc, base, iter, c); rc->rc_offset = physical_offset; rc->rc_abd = NULL; rc->rc_orig_data = NULL; rc->rc_error = 0; rc->rc_tried = 0; rc->rc_skipped = 0; rc->rc_force_repair = 0; rc->rc_allow_repair = 1; rc->rc_need_orig_restore = B_FALSE; if (q == 0 && i >= bc) rc->rc_size = 0; else if (i < bc) rc->rc_size = (q + 1) << ashift; else rc->rc_size = q << ashift; asize += rc->rc_size; } ASSERT3U(asize, ==, tot << ashift); rr->rr_nempty = roundup(tot, groupwidth) - tot; IMPLY(bc > 0, rr->rr_nempty == groupwidth - bc); /* Allocate buffers for the parity columns */ for (uint64_t c = 0; c < rr->rr_firstdatacol; c++) { raidz_col_t *rc = &rr->rr_col[c]; rc->rc_abd = abd_alloc_linear(rc->rc_size, B_FALSE); } /* * Map buffers for data columns and allocate/map buffers for skip * sectors. There are three distinct cases for dRAID which are * required to support sequential rebuild. */ if (zio->io_type == ZIO_TYPE_WRITE) { vdev_draid_map_alloc_write(zio, abd_offset, rr); } else if ((rr->rr_nempty > 0) && (zio->io_flags & (ZIO_FLAG_SCRUB | ZIO_FLAG_RESILVER))) { vdev_draid_map_alloc_scrub(zio, abd_offset, rr); } else { ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ); vdev_draid_map_alloc_read(zio, abd_offset, rr); } return (io_size); } /* * Allocate the raidz mapping to be applied to the dRAID I/O. The parity * calculations for dRAID are identical to raidz however there are a few * differences in the layout. * * - dRAID always allocates a full stripe width. Any extra sectors due * this padding are zero filled and written to disk. They will be read * back during a scrub or repair operation since they are included in * the parity calculation. This property enables sequential resilvering. * * - When the block at the logical offset spans redundancy groups then two * rows are allocated in the raidz_map_t. One row resides at the end of * the first group and the other at the start of the following group. */ static raidz_map_t * vdev_draid_map_alloc(zio_t *zio) { raidz_row_t *rr[2]; uint64_t abd_offset = 0; uint64_t abd_size = zio->io_size; uint64_t io_offset = zio->io_offset; uint64_t size; int nrows = 1; size = vdev_draid_map_alloc_row(zio, &rr[0], io_offset, abd_offset, abd_size); if (size < abd_size) { vdev_t *vd = zio->io_vd; io_offset += vdev_draid_asize(vd, size); abd_offset += size; abd_size -= size; nrows++; ASSERT3U(io_offset, ==, vdev_draid_group_to_offset( vd, vdev_draid_offset_to_group(vd, io_offset))); ASSERT3U(abd_offset, <, zio->io_size); ASSERT3U(abd_size, !=, 0); size = vdev_draid_map_alloc_row(zio, &rr[1], io_offset, abd_offset, abd_size); VERIFY3U(size, ==, abd_size); } raidz_map_t *rm; rm = kmem_zalloc(offsetof(raidz_map_t, rm_row[nrows]), KM_SLEEP); rm->rm_ops = vdev_raidz_math_get_ops(); rm->rm_nrows = nrows; rm->rm_row[0] = rr[0]; if (nrows == 2) rm->rm_row[1] = rr[1]; return (rm); } /* * Given an offset into a dRAID return the next group width aligned offset * which can be used to start an allocation. */ static uint64_t vdev_draid_get_astart(vdev_t *vd, const uint64_t start) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); return (roundup(start, vdc->vdc_groupwidth << vd->vdev_ashift)); } /* * Allocatable space for dRAID is (children - nspares) * sizeof(smallest child) * rounded down to the last full slice. So each child must provide at least * 1 / (children - nspares) of its asize. */ static uint64_t vdev_draid_min_asize(vdev_t *vd) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); return (VDEV_DRAID_REFLOW_RESERVE + (vd->vdev_min_asize + vdc->vdc_ndisks - 1) / (vdc->vdc_ndisks)); } /* * When using dRAID the minimum allocation size is determined by the number * of data disks in the redundancy group. Full stripes are always used. */ static uint64_t vdev_draid_min_alloc(vdev_t *vd) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); return (vdc->vdc_ndata << vd->vdev_ashift); } /* * Returns true if the txg range does not exist on any leaf vdev. * * A dRAID spare does not fit into the DTL model. While it has child vdevs * there is no redundancy among them, and the effective child vdev is * determined by offset. Essentially we do a vdev_dtl_reassess() on the * fly by replacing a dRAID spare with the child vdev under the offset. * Note that it is a recursive process because the child vdev can be * another dRAID spare and so on. */ boolean_t vdev_draid_missing(vdev_t *vd, uint64_t physical_offset, uint64_t txg, uint64_t size) { if (vd->vdev_ops == &vdev_spare_ops || vd->vdev_ops == &vdev_replacing_ops) { /* * Check all of the readable children, if any child * contains the txg range the data it is not missing. */ for (int c = 0; c < vd->vdev_children; c++) { vdev_t *cvd = vd->vdev_child[c]; if (!vdev_readable(cvd)) continue; if (!vdev_draid_missing(cvd, physical_offset, txg, size)) return (B_FALSE); } return (B_TRUE); } if (vd->vdev_ops == &vdev_draid_spare_ops) { /* * When sequentially resilvering we don't have a proper * txg range so instead we must presume all txgs are * missing on this vdev until the resilver completes. */ if (vd->vdev_rebuild_txg != 0) return (B_TRUE); /* * DTL_MISSING is set for all prior txgs when a resilver * is started in spa_vdev_attach(). */ if (vdev_dtl_contains(vd, DTL_MISSING, txg, size)) return (B_TRUE); /* * Consult the DTL on the relevant vdev. Either a vdev * leaf or spare/replace mirror child may be returned so * we must recursively call vdev_draid_missing_impl(). */ vd = vdev_draid_spare_get_child(vd, physical_offset); if (vd == NULL) return (B_TRUE); return (vdev_draid_missing(vd, physical_offset, txg, size)); } return (vdev_dtl_contains(vd, DTL_MISSING, txg, size)); } /* * Returns true if the txg is only partially replicated on the leaf vdevs. */ static boolean_t vdev_draid_partial(vdev_t *vd, uint64_t physical_offset, uint64_t txg, uint64_t size) { if (vd->vdev_ops == &vdev_spare_ops || vd->vdev_ops == &vdev_replacing_ops) { /* * Check all of the readable children, if any child is * missing the txg range then it is partially replicated. */ for (int c = 0; c < vd->vdev_children; c++) { vdev_t *cvd = vd->vdev_child[c]; if (!vdev_readable(cvd)) continue; if (vdev_draid_partial(cvd, physical_offset, txg, size)) return (B_TRUE); } return (B_FALSE); } if (vd->vdev_ops == &vdev_draid_spare_ops) { /* * When sequentially resilvering we don't have a proper * txg range so instead we must presume all txgs are * missing on this vdev until the resilver completes. */ if (vd->vdev_rebuild_txg != 0) return (B_TRUE); /* * DTL_MISSING is set for all prior txgs when a resilver * is started in spa_vdev_attach(). */ if (vdev_dtl_contains(vd, DTL_MISSING, txg, size)) return (B_TRUE); /* * Consult the DTL on the relevant vdev. Either a vdev * leaf or spare/replace mirror child may be returned so * we must recursively call vdev_draid_missing_impl(). */ vd = vdev_draid_spare_get_child(vd, physical_offset); if (vd == NULL) return (B_TRUE); return (vdev_draid_partial(vd, physical_offset, txg, size)); } return (vdev_dtl_contains(vd, DTL_MISSING, txg, size)); } /* * Determine if the vdev is readable at the given offset. */ boolean_t vdev_draid_readable(vdev_t *vd, uint64_t physical_offset) { if (vd->vdev_ops == &vdev_draid_spare_ops) { vd = vdev_draid_spare_get_child(vd, physical_offset); if (vd == NULL) return (B_FALSE); } if (vd->vdev_ops == &vdev_spare_ops || vd->vdev_ops == &vdev_replacing_ops) { for (int c = 0; c < vd->vdev_children; c++) { vdev_t *cvd = vd->vdev_child[c]; if (!vdev_readable(cvd)) continue; if (vdev_draid_readable(cvd, physical_offset)) return (B_TRUE); } return (B_FALSE); } return (vdev_readable(vd)); } /* * Returns the first distributed spare found under the provided vdev tree. */ static vdev_t * vdev_draid_find_spare(vdev_t *vd) { if (vd->vdev_ops == &vdev_draid_spare_ops) return (vd); for (int c = 0; c < vd->vdev_children; c++) { vdev_t *svd = vdev_draid_find_spare(vd->vdev_child[c]); if (svd != NULL) return (svd); } return (NULL); } /* * Returns B_TRUE if the passed in vdev is currently "faulted". * Faulted, in this context, means that the vdev represents a * replacing or sparing vdev tree. */ static boolean_t vdev_draid_faulted(vdev_t *vd, uint64_t physical_offset) { if (vd->vdev_ops == &vdev_draid_spare_ops) { vd = vdev_draid_spare_get_child(vd, physical_offset); if (vd == NULL) return (B_FALSE); /* * After resolving the distributed spare to a leaf vdev * check the parent to determine if it's "faulted". */ vd = vd->vdev_parent; } return (vd->vdev_ops == &vdev_replacing_ops || vd->vdev_ops == &vdev_spare_ops); } /* * Determine if the dRAID block at the logical offset is degraded. * Used by sequential resilver. */ static boolean_t vdev_draid_group_degraded(vdev_t *vd, uint64_t offset) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); ASSERT3U(vdev_draid_get_astart(vd, offset), ==, offset); uint64_t groupstart, perm; uint64_t physical_offset = vdev_draid_logical_to_physical(vd, offset, &perm, &groupstart); uint8_t *base; uint64_t iter; vdev_draid_get_perm(vdc, perm, &base, &iter); for (uint64_t i = 0; i < vdc->vdc_groupwidth; i++) { uint64_t c = (groupstart + i) % vdc->vdc_ndisks; uint64_t cid = vdev_draid_permute_id(vdc, base, iter, c); vdev_t *cvd = vd->vdev_child[cid]; /* Group contains a faulted vdev. */ if (vdev_draid_faulted(cvd, physical_offset)) return (B_TRUE); /* * Always check groups with active distributed spares * because any vdev failure in the pool will affect them. */ if (vdev_draid_find_spare(cvd) != NULL) return (B_TRUE); } return (B_FALSE); } /* * Determine if the txg is missing. Used by healing resilver. */ static boolean_t vdev_draid_group_missing(vdev_t *vd, uint64_t offset, uint64_t txg, uint64_t size) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); ASSERT3U(vdev_draid_get_astart(vd, offset), ==, offset); uint64_t groupstart, perm; uint64_t physical_offset = vdev_draid_logical_to_physical(vd, offset, &perm, &groupstart); uint8_t *base; uint64_t iter; vdev_draid_get_perm(vdc, perm, &base, &iter); for (uint64_t i = 0; i < vdc->vdc_groupwidth; i++) { uint64_t c = (groupstart + i) % vdc->vdc_ndisks; uint64_t cid = vdev_draid_permute_id(vdc, base, iter, c); vdev_t *cvd = vd->vdev_child[cid]; /* Transaction group is known to be partially replicated. */ if (vdev_draid_partial(cvd, physical_offset, txg, size)) return (B_TRUE); /* * Always check groups with active distributed spares * because any vdev failure in the pool will affect them. */ if (vdev_draid_find_spare(cvd) != NULL) return (B_TRUE); } return (B_FALSE); } /* * Find the smallest child asize and largest sector size to calculate the * available capacity. Distributed spares are ignored since their capacity * is also based of the minimum child size in the top-level dRAID. */ static void vdev_draid_calculate_asize(vdev_t *vd, uint64_t *asizep, uint64_t *max_asizep, uint64_t *logical_ashiftp, uint64_t *physical_ashiftp) { uint64_t logical_ashift = 0, physical_ashift = 0; uint64_t asize = 0, max_asize = 0; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); for (int c = 0; c < vd->vdev_children; c++) { vdev_t *cvd = vd->vdev_child[c]; if (cvd->vdev_ops == &vdev_draid_spare_ops) continue; asize = MIN(asize - 1, cvd->vdev_asize - 1) + 1; max_asize = MIN(max_asize - 1, cvd->vdev_max_asize - 1) + 1; logical_ashift = MAX(logical_ashift, cvd->vdev_ashift); } for (int c = 0; c < vd->vdev_children; c++) { vdev_t *cvd = vd->vdev_child[c]; if (cvd->vdev_ops == &vdev_draid_spare_ops) continue; physical_ashift = vdev_best_ashift(logical_ashift, physical_ashift, cvd->vdev_physical_ashift); } *asizep = asize; *max_asizep = max_asize; *logical_ashiftp = logical_ashift; *physical_ashiftp = physical_ashift; } /* * Open spare vdevs. */ static boolean_t vdev_draid_open_spares(vdev_t *vd) { return (vd->vdev_ops == &vdev_draid_spare_ops || vd->vdev_ops == &vdev_replacing_ops || vd->vdev_ops == &vdev_spare_ops); } /* * Open all children, excluding spares. */ static boolean_t vdev_draid_open_children(vdev_t *vd) { return (!vdev_draid_open_spares(vd)); } /* * Open a top-level dRAID vdev. */ static int vdev_draid_open(vdev_t *vd, uint64_t *asize, uint64_t *max_asize, uint64_t *logical_ashift, uint64_t *physical_ashift) { vdev_draid_config_t *vdc = vd->vdev_tsd; uint64_t nparity = vdc->vdc_nparity; int open_errors = 0; if (nparity > VDEV_DRAID_MAXPARITY || vd->vdev_children < nparity + 1) { vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL; return (SET_ERROR(EINVAL)); } /* * First open the normal children then the distributed spares. This * ordering is important to ensure the distributed spares calculate * the correct psize in the event that the dRAID vdevs were expanded. */ vdev_open_children_subset(vd, vdev_draid_open_children); vdev_open_children_subset(vd, vdev_draid_open_spares); /* Verify enough of the children are available to continue. */ for (int c = 0; c < vd->vdev_children; c++) { if (vd->vdev_child[c]->vdev_open_error != 0) { if ((++open_errors) > nparity) { vd->vdev_stat.vs_aux = VDEV_AUX_NO_REPLICAS; return (SET_ERROR(ENXIO)); } } } /* * Allocatable capacity is the sum of the space on all children less * the number of distributed spares rounded down to last full row * and then to the last full group. An additional 32MB of scratch * space is reserved at the end of each child for use by the dRAID * expansion feature. */ uint64_t child_asize, child_max_asize; vdev_draid_calculate_asize(vd, &child_asize, &child_max_asize, logical_ashift, physical_ashift); /* * Should be unreachable since the minimum child size is 64MB, but * we want to make sure an underflow absolutely cannot occur here. */ if (child_asize < VDEV_DRAID_REFLOW_RESERVE || child_max_asize < VDEV_DRAID_REFLOW_RESERVE) { return (SET_ERROR(ENXIO)); } child_asize = ((child_asize - VDEV_DRAID_REFLOW_RESERVE) / VDEV_DRAID_ROWHEIGHT) * VDEV_DRAID_ROWHEIGHT; child_max_asize = ((child_max_asize - VDEV_DRAID_REFLOW_RESERVE) / VDEV_DRAID_ROWHEIGHT) * VDEV_DRAID_ROWHEIGHT; *asize = (((child_asize * vdc->vdc_ndisks) / vdc->vdc_groupsz) * vdc->vdc_groupsz); *max_asize = (((child_max_asize * vdc->vdc_ndisks) / vdc->vdc_groupsz) * vdc->vdc_groupsz); return (0); } /* * Close a top-level dRAID vdev. */ static void vdev_draid_close(vdev_t *vd) { for (int c = 0; c < vd->vdev_children; c++) { if (vd->vdev_child[c] != NULL) vdev_close(vd->vdev_child[c]); } } /* * Return the maximum asize for a rebuild zio in the provided range * given the following constraints. A dRAID chunks may not: * * - Exceed the maximum allowed block size (SPA_MAXBLOCKSIZE), or * - Span dRAID redundancy groups. */ static uint64_t vdev_draid_rebuild_asize(vdev_t *vd, uint64_t start, uint64_t asize, uint64_t max_segment) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); uint64_t ashift = vd->vdev_ashift; uint64_t ndata = vdc->vdc_ndata; uint64_t psize = MIN(P2ROUNDUP(max_segment * ndata, 1 << ashift), SPA_MAXBLOCKSIZE); ASSERT3U(vdev_draid_get_astart(vd, start), ==, start); ASSERT3U(asize % (vdc->vdc_groupwidth << ashift), ==, 0); /* Chunks must evenly span all data columns in the group. */ psize = (((psize >> ashift) / ndata) * ndata) << ashift; uint64_t chunk_size = MIN(asize, vdev_psize_to_asize(vd, psize)); /* Reduce the chunk size to the group space remaining. */ uint64_t group = vdev_draid_offset_to_group(vd, start); uint64_t left = vdev_draid_group_to_offset(vd, group + 1) - start; chunk_size = MIN(chunk_size, left); ASSERT3U(chunk_size % (vdc->vdc_groupwidth << ashift), ==, 0); ASSERT3U(vdev_draid_offset_to_group(vd, start), ==, vdev_draid_offset_to_group(vd, start + chunk_size - 1)); return (chunk_size); } /* * Align the start of the metaslab to the group width and slightly reduce * its size to a multiple of the group width. Since full stripe writes are * required by dRAID this space is unallocable. Furthermore, aligning the * metaslab start is important for vdev initialize and TRIM which both operate * on metaslab boundaries which vdev_xlate() expects to be aligned. */ static void vdev_draid_metaslab_init(vdev_t *vd, uint64_t *ms_start, uint64_t *ms_size) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); uint64_t sz = vdc->vdc_groupwidth << vd->vdev_ashift; uint64_t astart = vdev_draid_get_astart(vd, *ms_start); uint64_t asize = ((*ms_size - (astart - *ms_start)) / sz) * sz; *ms_start = astart; *ms_size = asize; ASSERT0(*ms_start % sz); ASSERT0(*ms_size % sz); } /* * Add virtual dRAID spares to the list of valid spares. In order to accomplish * this the existing array must be freed and reallocated with the additional * entries. */ int vdev_draid_spare_create(nvlist_t *nvroot, vdev_t *vd, uint64_t *ndraidp, uint64_t next_vdev_id) { uint64_t draid_nspares = 0; uint64_t ndraid = 0; int error; for (uint64_t i = 0; i < vd->vdev_children; i++) { vdev_t *cvd = vd->vdev_child[i]; if (cvd->vdev_ops == &vdev_draid_ops) { vdev_draid_config_t *vdc = cvd->vdev_tsd; draid_nspares += vdc->vdc_nspares; ndraid++; } } if (draid_nspares == 0) { *ndraidp = ndraid; return (0); } nvlist_t **old_spares, **new_spares; uint_t old_nspares; error = nvlist_lookup_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES, &old_spares, &old_nspares); if (error) old_nspares = 0; /* Allocate memory and copy of the existing spares. */ new_spares = kmem_alloc(sizeof (nvlist_t *) * (draid_nspares + old_nspares), KM_SLEEP); for (uint_t i = 0; i < old_nspares; i++) new_spares[i] = fnvlist_dup(old_spares[i]); /* Add new distributed spares to ZPOOL_CONFIG_SPARES. */ uint64_t n = old_nspares; for (uint64_t vdev_id = 0; vdev_id < vd->vdev_children; vdev_id++) { vdev_t *cvd = vd->vdev_child[vdev_id]; char path[64]; if (cvd->vdev_ops != &vdev_draid_ops) continue; vdev_draid_config_t *vdc = cvd->vdev_tsd; uint64_t nspares = vdc->vdc_nspares; uint64_t nparity = vdc->vdc_nparity; for (uint64_t spare_id = 0; spare_id < nspares; spare_id++) { memset(path, 0, sizeof (path)); (void) snprintf(path, sizeof (path) - 1, "%s%llu-%llu-%llu", VDEV_TYPE_DRAID, (u_longlong_t)nparity, (u_longlong_t)next_vdev_id + vdev_id, (u_longlong_t)spare_id); nvlist_t *spare = fnvlist_alloc(); fnvlist_add_string(spare, ZPOOL_CONFIG_PATH, path); fnvlist_add_string(spare, ZPOOL_CONFIG_TYPE, VDEV_TYPE_DRAID_SPARE); fnvlist_add_uint64(spare, ZPOOL_CONFIG_TOP_GUID, cvd->vdev_guid); fnvlist_add_uint64(spare, ZPOOL_CONFIG_SPARE_ID, spare_id); fnvlist_add_uint64(spare, ZPOOL_CONFIG_IS_LOG, 0); fnvlist_add_uint64(spare, ZPOOL_CONFIG_IS_SPARE, 1); fnvlist_add_uint64(spare, ZPOOL_CONFIG_WHOLE_DISK, 1); fnvlist_add_uint64(spare, ZPOOL_CONFIG_ASHIFT, cvd->vdev_ashift); new_spares[n] = spare; n++; } } if (n > 0) { (void) nvlist_remove_all(nvroot, ZPOOL_CONFIG_SPARES); fnvlist_add_nvlist_array(nvroot, ZPOOL_CONFIG_SPARES, (const nvlist_t **)new_spares, n); } for (int i = 0; i < n; i++) nvlist_free(new_spares[i]); kmem_free(new_spares, sizeof (*new_spares) * n); *ndraidp = ndraid; return (0); } /* * Determine if any portion of the provided block resides on a child vdev * with a dirty DTL and therefore needs to be resilvered. */ static boolean_t vdev_draid_need_resilver(vdev_t *vd, const dva_t *dva, size_t psize, uint64_t phys_birth) { uint64_t offset = DVA_GET_OFFSET(dva); uint64_t asize = vdev_draid_asize(vd, psize); if (phys_birth == TXG_UNKNOWN) { /* * Sequential resilver. There is no meaningful phys_birth * for this block, we can only determine if block resides * in a degraded group in which case it must be resilvered. */ ASSERT3U(vdev_draid_offset_to_group(vd, offset), ==, vdev_draid_offset_to_group(vd, offset + asize - 1)); return (vdev_draid_group_degraded(vd, offset)); } else { /* * Healing resilver. TXGs not in DTL_PARTIAL are intact, * as are blocks in non-degraded groups. */ if (!vdev_dtl_contains(vd, DTL_PARTIAL, phys_birth, 1)) return (B_FALSE); if (vdev_draid_group_missing(vd, offset, phys_birth, 1)) return (B_TRUE); /* The block may span groups in which case check both. */ if (vdev_draid_offset_to_group(vd, offset) != vdev_draid_offset_to_group(vd, offset + asize - 1)) { if (vdev_draid_group_missing(vd, offset + asize, phys_birth, 1)) return (B_TRUE); } return (B_FALSE); } } static boolean_t vdev_draid_rebuilding(vdev_t *vd) { if (vd->vdev_ops->vdev_op_leaf && vd->vdev_rebuild_txg) return (B_TRUE); for (int i = 0; i < vd->vdev_children; i++) { if (vdev_draid_rebuilding(vd->vdev_child[i])) { return (B_TRUE); } } return (B_FALSE); } static void vdev_draid_io_verify(vdev_t *vd, raidz_row_t *rr, int col) { #ifdef ZFS_DEBUG range_seg64_t logical_rs, physical_rs, remain_rs; logical_rs.rs_start = rr->rr_offset; logical_rs.rs_end = logical_rs.rs_start + vdev_draid_asize(vd, rr->rr_size); raidz_col_t *rc = &rr->rr_col[col]; vdev_t *cvd = vd->vdev_child[rc->rc_devidx]; vdev_xlate(cvd, &logical_rs, &physical_rs, &remain_rs); ASSERT(vdev_xlate_is_empty(&remain_rs)); ASSERT3U(rc->rc_offset, ==, physical_rs.rs_start); ASSERT3U(rc->rc_offset, <, physical_rs.rs_end); ASSERT3U(rc->rc_offset + rc->rc_size, ==, physical_rs.rs_end); #endif } /* * For write operations: * 1. Generate the parity data * 2. Create child zio write operations to each column's vdev, for both * data and parity. A gang ABD is allocated by vdev_draid_map_alloc() * if a skip sector needs to be added to a column. */ static void vdev_draid_io_start_write(zio_t *zio, raidz_row_t *rr) { vdev_t *vd = zio->io_vd; raidz_map_t *rm = zio->io_vsd; vdev_raidz_generate_parity_row(rm, rr); for (int c = 0; c < rr->rr_cols; c++) { raidz_col_t *rc = &rr->rr_col[c]; /* * Empty columns are zero filled and included in the parity * calculation and therefore must be written. */ ASSERT3U(rc->rc_size, !=, 0); /* Verify physical to logical translation */ vdev_draid_io_verify(vd, rr, c); zio_nowait(zio_vdev_child_io(zio, NULL, vd->vdev_child[rc->rc_devidx], rc->rc_offset, rc->rc_abd, rc->rc_size, zio->io_type, zio->io_priority, 0, vdev_raidz_child_done, rc)); } } /* * For read operations: * 1. The vdev_draid_map_alloc() function will create a minimal raidz * mapping for the read based on the zio->io_flags. There are two * possible mappings either 1) a normal read, or 2) a scrub/resilver. * 2. Create the zio read operations. This will include all parity * columns and skip sectors for a scrub/resilver. */ static void vdev_draid_io_start_read(zio_t *zio, raidz_row_t *rr) { vdev_t *vd = zio->io_vd; /* Sequential rebuild must do IO at redundancy group boundary. */ IMPLY(zio->io_priority == ZIO_PRIORITY_REBUILD, rr->rr_nempty == 0); /* * Iterate over the columns in reverse order so that we hit the parity * last. Any errors along the way will force us to read the parity. * For scrub/resilver IOs which verify skip sectors, a gang ABD will * have been allocated to store them and rc->rc_size is increased. */ for (int c = rr->rr_cols - 1; c >= 0; c--) { raidz_col_t *rc = &rr->rr_col[c]; vdev_t *cvd = vd->vdev_child[rc->rc_devidx]; if (!vdev_draid_readable(cvd, rc->rc_offset)) { if (c >= rr->rr_firstdatacol) rr->rr_missingdata++; else rr->rr_missingparity++; rc->rc_error = SET_ERROR(ENXIO); rc->rc_tried = 1; rc->rc_skipped = 1; continue; } if (vdev_draid_missing(cvd, rc->rc_offset, zio->io_txg, 1)) { if (c >= rr->rr_firstdatacol) rr->rr_missingdata++; else rr->rr_missingparity++; rc->rc_error = SET_ERROR(ESTALE); rc->rc_skipped = 1; continue; } /* * Empty columns may be read during vdev_draid_io_done(). * Only skip them after the readable and missing checks * verify they are available. */ if (rc->rc_size == 0) { rc->rc_skipped = 1; continue; } if (zio->io_flags & ZIO_FLAG_RESILVER) { vdev_t *svd; /* * Sequential rebuilds need to always consider the data * on the child being rebuilt to be stale. This is * important when all columns are available to aid * known reconstruction in identifing which columns * contain incorrect data. * * Furthermore, all repairs need to be constrained to * the devices being rebuilt because without a checksum * we cannot verify the data is actually correct and * performing an incorrect repair could result in * locking in damage and making the data unrecoverable. */ if (zio->io_priority == ZIO_PRIORITY_REBUILD) { if (vdev_draid_rebuilding(cvd)) { if (c >= rr->rr_firstdatacol) rr->rr_missingdata++; else rr->rr_missingparity++; rc->rc_error = SET_ERROR(ESTALE); rc->rc_skipped = 1; rc->rc_allow_repair = 1; continue; } else { rc->rc_allow_repair = 0; } } else { rc->rc_allow_repair = 1; } /* * If this child is a distributed spare then the * offset might reside on the vdev being replaced. * In which case this data must be written to the * new device. Failure to do so would result in * checksum errors when the old device is detached * and the pool is scrubbed. */ if ((svd = vdev_draid_find_spare(cvd)) != NULL) { svd = vdev_draid_spare_get_child(svd, rc->rc_offset); if (svd && (svd->vdev_ops == &vdev_spare_ops || svd->vdev_ops == &vdev_replacing_ops)) { rc->rc_force_repair = 1; if (vdev_draid_rebuilding(svd)) rc->rc_allow_repair = 1; } } /* * Always issue a repair IO to this child when its * a spare or replacing vdev with an active rebuild. */ if ((cvd->vdev_ops == &vdev_spare_ops || cvd->vdev_ops == &vdev_replacing_ops) && vdev_draid_rebuilding(cvd)) { rc->rc_force_repair = 1; rc->rc_allow_repair = 1; } } } /* * Either a parity or data column is missing this means a repair * may be attempted by vdev_draid_io_done(). Expand the raid map * to read in empty columns which are needed along with the parity * during reconstruction. */ if ((rr->rr_missingdata > 0 || rr->rr_missingparity > 0) && rr->rr_nempty > 0 && rr->rr_abd_empty == NULL) { vdev_draid_map_alloc_empty(zio, rr); } for (int c = rr->rr_cols - 1; c >= 0; c--) { raidz_col_t *rc = &rr->rr_col[c]; vdev_t *cvd = vd->vdev_child[rc->rc_devidx]; if (rc->rc_error || rc->rc_size == 0) continue; if (c >= rr->rr_firstdatacol || rr->rr_missingdata > 0 || (zio->io_flags & (ZIO_FLAG_SCRUB | ZIO_FLAG_RESILVER))) { zio_nowait(zio_vdev_child_io(zio, NULL, cvd, rc->rc_offset, rc->rc_abd, rc->rc_size, zio->io_type, zio->io_priority, 0, vdev_raidz_child_done, rc)); } } } /* * Start an IO operation to a dRAID vdev. */ static void vdev_draid_io_start(zio_t *zio) { vdev_t *vd __maybe_unused = zio->io_vd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); ASSERT3U(zio->io_offset, ==, vdev_draid_get_astart(vd, zio->io_offset)); raidz_map_t *rm = vdev_draid_map_alloc(zio); zio->io_vsd = rm; zio->io_vsd_ops = &vdev_raidz_vsd_ops; if (zio->io_type == ZIO_TYPE_WRITE) { for (int i = 0; i < rm->rm_nrows; i++) { vdev_draid_io_start_write(zio, rm->rm_row[i]); } } else { ASSERT(zio->io_type == ZIO_TYPE_READ); for (int i = 0; i < rm->rm_nrows; i++) { vdev_draid_io_start_read(zio, rm->rm_row[i]); } } zio_execute(zio); } /* * Complete an IO operation on a dRAID vdev. The raidz logic can be applied * to dRAID since the layout is fully described by the raidz_map_t. */ static void vdev_draid_io_done(zio_t *zio) { vdev_raidz_io_done(zio); } static void vdev_draid_state_change(vdev_t *vd, int faulted, int degraded) { vdev_draid_config_t *vdc = vd->vdev_tsd; ASSERT(vd->vdev_ops == &vdev_draid_ops); if (faulted > vdc->vdc_nparity) vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN, VDEV_AUX_NO_REPLICAS); else if (degraded + faulted != 0) vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED, VDEV_AUX_NONE); else vdev_set_state(vd, B_FALSE, VDEV_STATE_HEALTHY, VDEV_AUX_NONE); } static void vdev_draid_xlate(vdev_t *cvd, const range_seg64_t *logical_rs, range_seg64_t *physical_rs, range_seg64_t *remain_rs) { vdev_t *raidvd = cvd->vdev_parent; ASSERT(raidvd->vdev_ops == &vdev_draid_ops); vdev_draid_config_t *vdc = raidvd->vdev_tsd; uint64_t ashift = raidvd->vdev_top->vdev_ashift; /* Make sure the offsets are block-aligned */ ASSERT0(logical_rs->rs_start % (1 << ashift)); ASSERT0(logical_rs->rs_end % (1 << ashift)); uint64_t logical_start = logical_rs->rs_start; uint64_t logical_end = logical_rs->rs_end; /* * Unaligned ranges must be skipped. All metaslabs are correctly * aligned so this should not happen, but this case is handled in * case it's needed by future callers. */ uint64_t astart = vdev_draid_get_astart(raidvd, logical_start); if (astart != logical_start) { physical_rs->rs_start = logical_start; physical_rs->rs_end = logical_start; remain_rs->rs_start = MIN(astart, logical_end); remain_rs->rs_end = logical_end; return; } /* * Unlike with mirrors and raidz a dRAID logical range can map * to multiple non-contiguous physical ranges. This is handled by * limiting the size of the logical range to a single group and * setting the remain argument such that it describes the remaining * unmapped logical range. This is stricter than absolutely * necessary but helps simplify the logic below. */ uint64_t group = vdev_draid_offset_to_group(raidvd, logical_start); uint64_t nextstart = vdev_draid_group_to_offset(raidvd, group + 1); if (logical_end > nextstart) logical_end = nextstart; /* Find the starting offset for each vdev in the group */ uint64_t perm, groupstart; uint64_t start = vdev_draid_logical_to_physical(raidvd, logical_start, &perm, &groupstart); uint64_t end = start; uint8_t *base; uint64_t iter, id; vdev_draid_get_perm(vdc, perm, &base, &iter); /* * Check if the passed child falls within the group. If it does * update the start and end to reflect the physical range. * Otherwise, leave them unmodified which will result in an empty * (zero-length) physical range being returned. */ for (uint64_t i = 0; i < vdc->vdc_groupwidth; i++) { uint64_t c = (groupstart + i) % vdc->vdc_ndisks; if (c == 0 && i != 0) { /* the group wrapped, increment the start */ start += VDEV_DRAID_ROWHEIGHT; end = start; } id = vdev_draid_permute_id(vdc, base, iter, c); if (id == cvd->vdev_id) { uint64_t b_size = (logical_end >> ashift) - (logical_start >> ashift); ASSERT3U(b_size, >, 0); end = start + ((((b_size - 1) / vdc->vdc_groupwidth) + 1) << ashift); break; } } physical_rs->rs_start = start; physical_rs->rs_end = end; /* * Only top-level vdevs are allowed to set remain_rs because * when .vdev_op_xlate() is called for their children the full * logical range is not provided by vdev_xlate(). */ remain_rs->rs_start = logical_end; remain_rs->rs_end = logical_rs->rs_end; ASSERT3U(physical_rs->rs_start, <=, logical_start); ASSERT3U(physical_rs->rs_end - physical_rs->rs_start, <=, logical_end - logical_start); } /* * Add dRAID specific fields to the config nvlist. */ static void vdev_draid_config_generate(vdev_t *vd, nvlist_t *nv) { ASSERT3P(vd->vdev_ops, ==, &vdev_draid_ops); vdev_draid_config_t *vdc = vd->vdev_tsd; fnvlist_add_uint64(nv, ZPOOL_CONFIG_NPARITY, vdc->vdc_nparity); fnvlist_add_uint64(nv, ZPOOL_CONFIG_DRAID_NDATA, vdc->vdc_ndata); fnvlist_add_uint64(nv, ZPOOL_CONFIG_DRAID_NSPARES, vdc->vdc_nspares); fnvlist_add_uint64(nv, ZPOOL_CONFIG_DRAID_NGROUPS, vdc->vdc_ngroups); } /* * Initialize private dRAID specific fields from the nvlist. */ static int vdev_draid_init(spa_t *spa, nvlist_t *nv, void **tsd) { (void) spa; uint64_t ndata, nparity, nspares, ngroups; int error; if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_DRAID_NDATA, &ndata)) return (SET_ERROR(EINVAL)); if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_NPARITY, &nparity) || nparity == 0 || nparity > VDEV_DRAID_MAXPARITY) { return (SET_ERROR(EINVAL)); } uint_t children; nvlist_t **child; if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_CHILDREN, &child, &children) != 0 || children == 0 || children > VDEV_DRAID_MAX_CHILDREN) { return (SET_ERROR(EINVAL)); } if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_DRAID_NSPARES, &nspares) || nspares > 100 || nspares > (children - (ndata + nparity))) { return (SET_ERROR(EINVAL)); } if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_DRAID_NGROUPS, &ngroups) || ngroups == 0 || ngroups > VDEV_DRAID_MAX_CHILDREN) { return (SET_ERROR(EINVAL)); } /* * Validate the minimum number of children exist per group for the * specified parity level (draid1 >= 2, draid2 >= 3, draid3 >= 4). */ if (children < (ndata + nparity + nspares)) return (SET_ERROR(EINVAL)); /* * Create the dRAID configuration using the pool nvlist configuration * and the fixed mapping for the correct number of children. */ vdev_draid_config_t *vdc; const draid_map_t *map; error = vdev_draid_lookup_map(children, &map); if (error) return (SET_ERROR(EINVAL)); vdc = kmem_zalloc(sizeof (*vdc), KM_SLEEP); vdc->vdc_ndata = ndata; vdc->vdc_nparity = nparity; vdc->vdc_nspares = nspares; vdc->vdc_children = children; vdc->vdc_ngroups = ngroups; vdc->vdc_nperms = map->dm_nperms; error = vdev_draid_generate_perms(map, &vdc->vdc_perms); if (error) { kmem_free(vdc, sizeof (*vdc)); return (SET_ERROR(EINVAL)); } /* * Derived constants. */ vdc->vdc_groupwidth = vdc->vdc_ndata + vdc->vdc_nparity; vdc->vdc_ndisks = vdc->vdc_children - vdc->vdc_nspares; vdc->vdc_groupsz = vdc->vdc_groupwidth * VDEV_DRAID_ROWHEIGHT; vdc->vdc_devslicesz = (vdc->vdc_groupsz * vdc->vdc_ngroups) / vdc->vdc_ndisks; ASSERT3U(vdc->vdc_groupwidth, >=, 2); ASSERT3U(vdc->vdc_groupwidth, <=, vdc->vdc_ndisks); ASSERT3U(vdc->vdc_groupsz, >=, 2 * VDEV_DRAID_ROWHEIGHT); ASSERT3U(vdc->vdc_devslicesz, >=, VDEV_DRAID_ROWHEIGHT); ASSERT3U(vdc->vdc_devslicesz % VDEV_DRAID_ROWHEIGHT, ==, 0); ASSERT3U((vdc->vdc_groupwidth * vdc->vdc_ngroups) % vdc->vdc_ndisks, ==, 0); *tsd = vdc; return (0); } static void vdev_draid_fini(vdev_t *vd) { vdev_draid_config_t *vdc = vd->vdev_tsd; vmem_free(vdc->vdc_perms, sizeof (uint8_t) * vdc->vdc_children * vdc->vdc_nperms); kmem_free(vdc, sizeof (*vdc)); } static uint64_t vdev_draid_nparity(vdev_t *vd) { vdev_draid_config_t *vdc = vd->vdev_tsd; return (vdc->vdc_nparity); } static uint64_t vdev_draid_ndisks(vdev_t *vd) { vdev_draid_config_t *vdc = vd->vdev_tsd; return (vdc->vdc_ndisks); } vdev_ops_t vdev_draid_ops = { .vdev_op_init = vdev_draid_init, .vdev_op_fini = vdev_draid_fini, .vdev_op_open = vdev_draid_open, .vdev_op_close = vdev_draid_close, .vdev_op_asize = vdev_draid_asize, .vdev_op_min_asize = vdev_draid_min_asize, .vdev_op_min_alloc = vdev_draid_min_alloc, .vdev_op_io_start = vdev_draid_io_start, .vdev_op_io_done = vdev_draid_io_done, .vdev_op_state_change = vdev_draid_state_change, .vdev_op_need_resilver = vdev_draid_need_resilver, .vdev_op_hold = NULL, .vdev_op_rele = NULL, .vdev_op_remap = NULL, .vdev_op_xlate = vdev_draid_xlate, .vdev_op_rebuild_asize = vdev_draid_rebuild_asize, .vdev_op_metaslab_init = vdev_draid_metaslab_init, .vdev_op_config_generate = vdev_draid_config_generate, .vdev_op_nparity = vdev_draid_nparity, .vdev_op_ndisks = vdev_draid_ndisks, .vdev_op_type = VDEV_TYPE_DRAID, .vdev_op_leaf = B_FALSE, }; /* * A dRAID distributed spare is a virtual leaf vdev which is included in the * parent dRAID configuration. The last N columns of the dRAID permutation * table are used to determine on which dRAID children a specific offset * should be written. These spare leaf vdevs can only be used to replace * faulted children in the same dRAID configuration. */ /* * Distributed spare state. All fields are set when the distributed spare is * first opened and are immutable. */ typedef struct { vdev_t *vds_draid_vdev; /* top-level parent dRAID vdev */ uint64_t vds_top_guid; /* top-level parent dRAID guid */ uint64_t vds_spare_id; /* spare id (0 - vdc->vdc_nspares-1) */ } vdev_draid_spare_t; /* * Returns the parent dRAID vdev to which the distributed spare belongs. * This may be safely called even when the vdev is not open. */ vdev_t * vdev_draid_spare_get_parent(vdev_t *vd) { vdev_draid_spare_t *vds = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_spare_ops); if (vds->vds_draid_vdev != NULL) return (vds->vds_draid_vdev); return (vdev_lookup_by_guid(vd->vdev_spa->spa_root_vdev, vds->vds_top_guid)); } /* * A dRAID space is active when it's the child of a vdev using the * vdev_spare_ops, vdev_replacing_ops or vdev_draid_ops. */ static boolean_t vdev_draid_spare_is_active(vdev_t *vd) { vdev_t *pvd = vd->vdev_parent; if (pvd != NULL && (pvd->vdev_ops == &vdev_spare_ops || pvd->vdev_ops == &vdev_replacing_ops || pvd->vdev_ops == &vdev_draid_ops)) { return (B_TRUE); } else { return (B_FALSE); } } /* * Given a dRAID distribute spare vdev, returns the physical child vdev * on which the provided offset resides. This may involve recursing through * multiple layers of distributed spares. Note that offset is relative to * this vdev. */ vdev_t * vdev_draid_spare_get_child(vdev_t *vd, uint64_t physical_offset) { vdev_draid_spare_t *vds = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_spare_ops); /* The vdev is closed */ if (vds->vds_draid_vdev == NULL) return (NULL); vdev_t *tvd = vds->vds_draid_vdev; vdev_draid_config_t *vdc = tvd->vdev_tsd; ASSERT3P(tvd->vdev_ops, ==, &vdev_draid_ops); ASSERT3U(vds->vds_spare_id, <, vdc->vdc_nspares); uint8_t *base; uint64_t iter; uint64_t perm = physical_offset / vdc->vdc_devslicesz; vdev_draid_get_perm(vdc, perm, &base, &iter); uint64_t cid = vdev_draid_permute_id(vdc, base, iter, (tvd->vdev_children - 1) - vds->vds_spare_id); vdev_t *cvd = tvd->vdev_child[cid]; if (cvd->vdev_ops == &vdev_draid_spare_ops) return (vdev_draid_spare_get_child(cvd, physical_offset)); return (cvd); } static void vdev_draid_spare_close(vdev_t *vd) { vdev_draid_spare_t *vds = vd->vdev_tsd; vds->vds_draid_vdev = NULL; } /* * Opening a dRAID spare device is done by looking up the associated dRAID * top-level vdev guid from the spare configuration. */ static int vdev_draid_spare_open(vdev_t *vd, uint64_t *psize, uint64_t *max_psize, uint64_t *logical_ashift, uint64_t *physical_ashift) { vdev_draid_spare_t *vds = vd->vdev_tsd; vdev_t *rvd = vd->vdev_spa->spa_root_vdev; uint64_t asize, max_asize; vdev_t *tvd = vdev_lookup_by_guid(rvd, vds->vds_top_guid); if (tvd == NULL) { /* * When spa_vdev_add() is labeling new spares the * associated dRAID is not attached to the root vdev * nor does this spare have a parent. Simulate a valid * device in order to allow the label to be initialized * and the distributed spare added to the configuration. */ if (vd->vdev_parent == NULL) { *psize = *max_psize = SPA_MINDEVSIZE; *logical_ashift = *physical_ashift = ASHIFT_MIN; return (0); } return (SET_ERROR(EINVAL)); } vdev_draid_config_t *vdc = tvd->vdev_tsd; if (tvd->vdev_ops != &vdev_draid_ops || vdc == NULL) return (SET_ERROR(EINVAL)); if (vds->vds_spare_id >= vdc->vdc_nspares) return (SET_ERROR(EINVAL)); /* * Neither tvd->vdev_asize or tvd->vdev_max_asize can be used here * because the caller may be vdev_draid_open() in which case the * values are stale as they haven't yet been updated by vdev_open(). * To avoid this always recalculate the dRAID asize and max_asize. */ vdev_draid_calculate_asize(tvd, &asize, &max_asize, logical_ashift, physical_ashift); *psize = asize + VDEV_LABEL_START_SIZE + VDEV_LABEL_END_SIZE; *max_psize = max_asize + VDEV_LABEL_START_SIZE + VDEV_LABEL_END_SIZE; vds->vds_draid_vdev = tvd; return (0); } /* * Completed distributed spare IO. Store the result in the parent zio * as if it had performed the operation itself. Only the first error is * preserved if there are multiple errors. */ static void vdev_draid_spare_child_done(zio_t *zio) { zio_t *pio = zio->io_private; /* * IOs are issued to non-writable vdevs in order to keep their * DTLs accurate. However, we don't want to propagate the * error in to the distributed spare's DTL. When resilvering * vdev_draid_need_resilver() will consult the relevant DTL * to determine if the data is missing and must be repaired. */ if (!vdev_writeable(zio->io_vd)) return; if (pio->io_error == 0) pio->io_error = zio->io_error; } /* * Returns a valid label nvlist for the distributed spare vdev. This is * used to bypass the IO pipeline to avoid the complexity of constructing * a complete label with valid checksum to return when read. */ nvlist_t * vdev_draid_read_config_spare(vdev_t *vd) { spa_t *spa = vd->vdev_spa; spa_aux_vdev_t *sav = &spa->spa_spares; uint64_t guid = vd->vdev_guid; nvlist_t *nv = fnvlist_alloc(); fnvlist_add_uint64(nv, ZPOOL_CONFIG_IS_SPARE, 1); fnvlist_add_uint64(nv, ZPOOL_CONFIG_CREATE_TXG, vd->vdev_crtxg); fnvlist_add_uint64(nv, ZPOOL_CONFIG_VERSION, spa_version(spa)); fnvlist_add_string(nv, ZPOOL_CONFIG_POOL_NAME, spa_name(spa)); fnvlist_add_uint64(nv, ZPOOL_CONFIG_POOL_GUID, spa_guid(spa)); fnvlist_add_uint64(nv, ZPOOL_CONFIG_POOL_TXG, spa->spa_config_txg); fnvlist_add_uint64(nv, ZPOOL_CONFIG_TOP_GUID, vd->vdev_top->vdev_guid); fnvlist_add_uint64(nv, ZPOOL_CONFIG_POOL_STATE, vdev_draid_spare_is_active(vd) ? POOL_STATE_ACTIVE : POOL_STATE_SPARE); /* Set the vdev guid based on the vdev list in sav_count. */ for (int i = 0; i < sav->sav_count; i++) { if (sav->sav_vdevs[i]->vdev_ops == &vdev_draid_spare_ops && strcmp(sav->sav_vdevs[i]->vdev_path, vd->vdev_path) == 0) { guid = sav->sav_vdevs[i]->vdev_guid; break; } } fnvlist_add_uint64(nv, ZPOOL_CONFIG_GUID, guid); return (nv); } /* * Handle any ioctl requested of the distributed spare. Only flushes * are supported in which case all children must be flushed. */ static int vdev_draid_spare_ioctl(zio_t *zio) { vdev_t *vd = zio->io_vd; int error = 0; if (zio->io_cmd == DKIOCFLUSHWRITECACHE) { for (int c = 0; c < vd->vdev_children; c++) { zio_nowait(zio_vdev_child_io(zio, NULL, vd->vdev_child[c], zio->io_offset, zio->io_abd, zio->io_size, zio->io_type, zio->io_priority, 0, vdev_draid_spare_child_done, zio)); } } else { error = SET_ERROR(ENOTSUP); } return (error); } /* * Initiate an IO to the distributed spare. For normal IOs this entails using * the zio->io_offset and permutation table to calculate which child dRAID vdev * is responsible for the data. Then passing along the zio to that child to * perform the actual IO. The label ranges are not stored on disk and require * some special handling which is described below. */ static void vdev_draid_spare_io_start(zio_t *zio) { vdev_t *cvd = NULL, *vd = zio->io_vd; vdev_draid_spare_t *vds = vd->vdev_tsd; uint64_t offset = zio->io_offset - VDEV_LABEL_START_SIZE; /* * If the vdev is closed, it's likely in the REMOVED or FAULTED state. * Nothing to be done here but return failure. */ if (vds == NULL) { zio->io_error = ENXIO; zio_interrupt(zio); return; } switch (zio->io_type) { case ZIO_TYPE_IOCTL: zio->io_error = vdev_draid_spare_ioctl(zio); break; case ZIO_TYPE_WRITE: if (VDEV_OFFSET_IS_LABEL(vd, zio->io_offset)) { /* * Accept probe IOs and config writers to simulate the * existence of an on disk label. vdev_label_sync(), * vdev_uberblock_sync() and vdev_copy_uberblocks() * skip the distributed spares. This only leaves * vdev_label_init() which is allowed to succeed to * avoid adding special cases the function. */ if (zio->io_flags & ZIO_FLAG_PROBE || zio->io_flags & ZIO_FLAG_CONFIG_WRITER) { zio->io_error = 0; } else { zio->io_error = SET_ERROR(EIO); } } else { cvd = vdev_draid_spare_get_child(vd, offset); if (cvd == NULL) { zio->io_error = SET_ERROR(ENXIO); } else { zio_nowait(zio_vdev_child_io(zio, NULL, cvd, offset, zio->io_abd, zio->io_size, zio->io_type, zio->io_priority, 0, vdev_draid_spare_child_done, zio)); } } break; case ZIO_TYPE_READ: if (VDEV_OFFSET_IS_LABEL(vd, zio->io_offset)) { /* * Accept probe IOs to simulate the existence of a * label. vdev_label_read_config() bypasses the * pipeline to read the label configuration and * vdev_uberblock_load() skips distributed spares * when attempting to locate the best uberblock. */ if (zio->io_flags & ZIO_FLAG_PROBE) { zio->io_error = 0; } else { zio->io_error = SET_ERROR(EIO); } } else { cvd = vdev_draid_spare_get_child(vd, offset); if (cvd == NULL || !vdev_readable(cvd)) { zio->io_error = SET_ERROR(ENXIO); } else { zio_nowait(zio_vdev_child_io(zio, NULL, cvd, offset, zio->io_abd, zio->io_size, zio->io_type, zio->io_priority, 0, vdev_draid_spare_child_done, zio)); } } break; case ZIO_TYPE_TRIM: /* The vdev label ranges are never trimmed */ ASSERT0(VDEV_OFFSET_IS_LABEL(vd, zio->io_offset)); cvd = vdev_draid_spare_get_child(vd, offset); if (cvd == NULL || !cvd->vdev_has_trim) { zio->io_error = SET_ERROR(ENXIO); } else { zio_nowait(zio_vdev_child_io(zio, NULL, cvd, offset, zio->io_abd, zio->io_size, zio->io_type, zio->io_priority, 0, vdev_draid_spare_child_done, zio)); } break; default: zio->io_error = SET_ERROR(ENOTSUP); break; } zio_execute(zio); } static void vdev_draid_spare_io_done(zio_t *zio) { (void) zio; } /* * Lookup the full spare config in spa->spa_spares.sav_config and * return the top_guid and spare_id for the named spare. */ static int vdev_draid_spare_lookup(spa_t *spa, nvlist_t *nv, uint64_t *top_guidp, uint64_t *spare_idp) { nvlist_t **spares; uint_t nspares; int error; if ((spa->spa_spares.sav_config == NULL) || (nvlist_lookup_nvlist_array(spa->spa_spares.sav_config, ZPOOL_CONFIG_SPARES, &spares, &nspares) != 0)) { return (SET_ERROR(ENOENT)); } char *spare_name; error = nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &spare_name); if (error != 0) return (SET_ERROR(EINVAL)); for (int i = 0; i < nspares; i++) { nvlist_t *spare = spares[i]; uint64_t top_guid, spare_id; char *type, *path; /* Skip non-distributed spares */ error = nvlist_lookup_string(spare, ZPOOL_CONFIG_TYPE, &type); if (error != 0 || strcmp(type, VDEV_TYPE_DRAID_SPARE) != 0) continue; /* Skip spares with the wrong name */ error = nvlist_lookup_string(spare, ZPOOL_CONFIG_PATH, &path); if (error != 0 || strcmp(path, spare_name) != 0) continue; /* Found the matching spare */ error = nvlist_lookup_uint64(spare, ZPOOL_CONFIG_TOP_GUID, &top_guid); if (error == 0) { error = nvlist_lookup_uint64(spare, ZPOOL_CONFIG_SPARE_ID, &spare_id); } if (error != 0) { return (SET_ERROR(EINVAL)); } else { *top_guidp = top_guid; *spare_idp = spare_id; return (0); } } return (SET_ERROR(ENOENT)); } /* * Initialize private dRAID spare specific fields from the nvlist. */ static int vdev_draid_spare_init(spa_t *spa, nvlist_t *nv, void **tsd) { vdev_draid_spare_t *vds; uint64_t top_guid = 0; uint64_t spare_id; /* * In the normal case check the list of spares stored in the spa * to lookup the top_guid and spare_id for provided spare config. * When creating a new pool or adding vdevs the spare list is not * yet populated and the values are provided in the passed config. */ if (vdev_draid_spare_lookup(spa, nv, &top_guid, &spare_id) != 0) { if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_TOP_GUID, &top_guid) != 0) return (SET_ERROR(EINVAL)); if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_SPARE_ID, &spare_id) != 0) return (SET_ERROR(EINVAL)); } vds = kmem_alloc(sizeof (vdev_draid_spare_t), KM_SLEEP); vds->vds_draid_vdev = NULL; vds->vds_top_guid = top_guid; vds->vds_spare_id = spare_id; *tsd = vds; return (0); } static void vdev_draid_spare_fini(vdev_t *vd) { kmem_free(vd->vdev_tsd, sizeof (vdev_draid_spare_t)); } static void vdev_draid_spare_config_generate(vdev_t *vd, nvlist_t *nv) { vdev_draid_spare_t *vds = vd->vdev_tsd; ASSERT3P(vd->vdev_ops, ==, &vdev_draid_spare_ops); fnvlist_add_uint64(nv, ZPOOL_CONFIG_TOP_GUID, vds->vds_top_guid); fnvlist_add_uint64(nv, ZPOOL_CONFIG_SPARE_ID, vds->vds_spare_id); } vdev_ops_t vdev_draid_spare_ops = { .vdev_op_init = vdev_draid_spare_init, .vdev_op_fini = vdev_draid_spare_fini, .vdev_op_open = vdev_draid_spare_open, .vdev_op_close = vdev_draid_spare_close, .vdev_op_asize = vdev_default_asize, .vdev_op_min_asize = vdev_default_min_asize, .vdev_op_min_alloc = NULL, .vdev_op_io_start = vdev_draid_spare_io_start, .vdev_op_io_done = vdev_draid_spare_io_done, .vdev_op_state_change = NULL, .vdev_op_need_resilver = NULL, .vdev_op_hold = NULL, .vdev_op_rele = NULL, .vdev_op_remap = NULL, .vdev_op_xlate = vdev_default_xlate, .vdev_op_rebuild_asize = NULL, .vdev_op_metaslab_init = NULL, .vdev_op_config_generate = vdev_draid_spare_config_generate, .vdev_op_nparity = NULL, .vdev_op_ndisks = NULL, .vdev_op_type = VDEV_TYPE_DRAID_SPARE, .vdev_op_leaf = B_TRUE, };