| 1 | |
| 2 | |
| 3 | * Partial Parity Log for closing the RAID5 write hole
|
| 4 | * Copyright (c) 2017, Intel Corporation.
|
| 5 |
|
| 6 |
|
| 7 | #include <linux/kernel.h>
|
| 8 | #include <linux/blkdev.h>
|
| 9 | #include <linux/slab.h>
|
| 10 | #include <linux/crc32c.h>
|
| 11 | #include <linux/async_tx.h>
|
| 12 | #include <linux/raid/md_p.h>
|
| 13 | #include "md.h"
|
| 14 | #include "raid5.h"
|
| 15 | #include "raid5-log.h"
|
| 16 |
|
| 17 | |
| 18 | * PPL consists of a 4KB header (struct ppl_header) and at least 128KB for
|
| 19 | * partial parity data. The header contains an array of entries
|
| 20 | * (struct ppl_header_entry) which describe the logged write requests.
|
| 21 | * Partial parity for the entries comes after the header, written in the same
|
| 22 | * sequence as the entries:
|
| 23 | *
|
| 24 | * Header
|
| 25 | * entry0
|
| 26 | * ...
|
| 27 | * entryN
|
| 28 | * PP data
|
| 29 | * PP for entry0
|
| 30 | * ...
|
| 31 | * PP for entryN
|
| 32 | *
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| 33 | * An entry describes one or more consecutive stripe_heads, up to a full
|
| 34 | * stripe. The modifed raid data chunks form an m-by-n matrix, where m is the
|
| 35 | * number of stripe_heads in the entry and n is the number of modified data
|
| 36 | * disks. Every stripe_head in the entry must write to the same data disks.
|
| 37 | * An example of a valid case described by a single entry (writes to the first
|
| 38 | * stripe of a 4 disk array, 16k chunk size):
|
| 39 | *
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| 40 | * sh->sector dd0 dd1 dd2 ppl
|
| 41 | * +-----+-----+-----+
|
| 42 | * 0 | --- | --- | --- | +----+
|
| 43 | * 8 | -W- | -W- | --- | | pp | data_sector = 8
|
| 44 | * 16 | -W- | -W- | --- | | pp | data_size = 3 * 2 * 4k
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| 45 | * 24 | -W- | -W- | --- | | pp | pp_size = 3 * 4k
|
| 46 | * +-----+-----+-----+ +----+
|
| 47 | *
|
| 48 | * data_sector is the first raid sector of the modified data, data_size is the
|
| 49 | * total size of modified data and pp_size is the size of partial parity for
|
| 50 | * this entry. Entries for full stripe writes contain no partial parity
|
| 51 | * (pp_size = 0), they only mark the stripes for which parity should be
|
| 52 | * recalculated after an unclean shutdown. Every entry holds a checksum of its
|
| 53 | * partial parity, the header also has a checksum of the header itself.
|
| 54 | *
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| 55 | * A write request is always logged to the PPL instance stored on the parity
|
| 56 | * disk of the corresponding stripe. For each member disk there is one ppl_log
|
| 57 | * used to handle logging for this disk, independently from others. They are
|
| 58 | * grouped in child_logs array in struct ppl_conf, which is assigned to
|
| 59 | * r5conf->log_private.
|
| 60 | *
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| 61 | * ppl_io_unit represents a full PPL write, header_page contains the ppl_header.
|
| 62 | * PPL entries for logged stripes are added in ppl_log_stripe(). A stripe_head
|
| 63 | * can be appended to the last entry if it meets the conditions for a valid
|
| 64 | * entry described above, otherwise a new entry is added. Checksums of entries
|
| 65 | * are calculated incrementally as stripes containing partial parity are being
|
| 66 | * added. ppl_submit_iounit() calculates the checksum of the header and submits
|
| 67 | * a bio containing the header page and partial parity pages (sh->ppl_page) for
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| 68 | * all stripes of the io_unit. When the PPL write completes, the stripes
|
| 69 | * associated with the io_unit are released and raid5d starts writing their data
|
| 70 | * and parity. When all stripes are written, the io_unit is freed and the next
|
| 71 | * can be submitted.
|
| 72 | *
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| 73 | * An io_unit is used to gather stripes until it is submitted or becomes full
|
| 74 | * (if the maximum number of entries or size of PPL is reached). Another io_unit
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| 75 | * can't be submitted until the previous has completed (PPL and stripe
|
| 76 | * data+parity is written). The log->io_list tracks all io_units of a log
|
| 77 | * (for a single member disk). New io_units are added to the end of the list
|
| 78 | * and the first io_unit is submitted, if it is not submitted already.
|
| 79 | * The current io_unit accepting new stripes is always at the end of the list.
|
| 80 | *
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| 81 | * If write-back cache is enabled for any of the disks in the array, its data
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| 82 | * must be flushed before next io_unit is submitted.
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| 83 |
|
| 84 |
|
| 85 | #define PPL_SPACE_SIZE (128 * 1024)
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| 86 |
|
| 87 | struct ppl_conf {
|
| 88 | struct mddev *mddev;
|
| 89 |
|
| 90 |
|
| 91 | struct ppl_log *child_logs;
|
| 92 | int count;
|
| 93 |
|
| 94 | int block_size; |
| 95 | * in ppl_header_entry
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| 96 | u32 signature;
|
| 97 | atomic64_t seq;
|
| 98 |
|
| 99 | struct kmem_cache *io_kc;
|
| 100 | mempool_t io_pool;
|
| 101 | struct bio_set bs;
|
| 102 | struct bio_set flush_bs;
|
| 103 |
|
| 104 |
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| 105 | int recovered_entries;
|
| 106 | int mismatch_count;
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| 107 |
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| 108 |
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| 109 | struct list_head no_mem_stripes;
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| 110 | spinlock_t no_mem_stripes_lock;
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| 111 |
|
| 112 | unsigned short write_hint;
|
| 113 | };
|
| 114 |
|
| 115 | struct ppl_log {
|
| 116 | struct ppl_conf *ppl_conf;
|
| 117 |
|
| 118 | struct md_rdev *rdev; |
| 119 | * this log instance
|
| 120 | struct mutex io_mutex;
|
| 121 | struct ppl_io_unit *current_io; |
| 122 | * always at the end of io_list
|
| 123 | spinlock_t io_list_lock;
|
| 124 | struct list_head io_list;
|
| 125 |
|
| 126 | sector_t next_io_sector;
|
| 127 | unsigned int entry_space;
|
| 128 | bool use_multippl;
|
| 129 | bool wb_cache_on;
|
| 130 | unsigned long disk_flush_bitmap;
|
| 131 | };
|
| 132 |
|
| 133 | #define PPL_IO_INLINE_BVECS 32
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| 134 |
|
| 135 | struct ppl_io_unit {
|
| 136 | struct ppl_log *log;
|
| 137 |
|
| 138 | struct page *header_page;
|
| 139 |
|
| 140 | unsigned int entries_count;
|
| 141 | unsigned int pp_size;
|
| 142 |
|
| 143 | u64 seq;
|
| 144 | struct list_head log_sibling;
|
| 145 |
|
| 146 | struct list_head stripe_list;
|
| 147 | atomic_t pending_stripes;
|
| 148 | atomic_t pending_flushes;
|
| 149 |
|
| 150 | bool submitted;
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| 151 |
|
| 152 |
|
| 153 | struct bio bio;
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| 154 | struct bio_vec biovec[PPL_IO_INLINE_BVECS];
|
| 155 | };
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| 156 |
|
| 157 | struct dma_async_tx_descriptor *
|
| 158 | ops_run_partial_parity(struct stripe_head *sh, struct raid5_percpu *percpu,
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| 159 | struct dma_async_tx_descriptor *tx)
|
| 160 | {
|
| 161 | int disks = sh->disks;
|
| 162 | struct page **srcs = percpu->scribble;
|
| 163 | int count = 0, pd_idx = sh->pd_idx, i;
|
| 164 | struct async_submit_ctl submit;
|
| 165 |
|
| 166 | pr_debug("%s: stripe %llu\n", __func__, (unsigned long long)sh->sector);
|
| 167 |
|
| 168 | |
| 169 | * Partial parity is the XOR of stripe data chunks that are not changed
|
| 170 | * during the write request. Depending on available data
|
| 171 | * (read-modify-write vs. reconstruct-write case) we calculate it
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| 172 | * differently.
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| 173 |
|
| 174 | if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) {
|
| 175 | |
| 176 | * rmw: xor old data and parity from updated disks
|
| 177 | * This is calculated earlier by ops_run_prexor5() so just copy
|
| 178 | * the parity dev page.
|
| 179 |
|
| 180 | srcs[count++] = sh->dev[pd_idx].page;
|
| 181 | } else if (sh->reconstruct_state == reconstruct_state_drain_run) {
|
| 182 |
|
| 183 | for (i = disks; i--;) {
|
| 184 | struct r5dev *dev = &sh->dev[i];
|
| 185 | if (test_bit(R5_UPTODATE, &dev->flags))
|
| 186 | srcs[count++] = dev->page;
|
| 187 | }
|
| 188 | } else {
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| 189 | return tx;
|
| 190 | }
|
| 191 |
|
| 192 | init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, tx,
|
| 193 | NULL, sh, (void *) (srcs + sh->disks + 2));
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| 194 |
|
| 195 | if (count == 1)
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| 196 | tx = async_memcpy(sh->ppl_page, srcs[0], 0, 0, PAGE_SIZE,
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| 197 | &submit);
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| 198 | else
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| 199 | tx = async_xor(sh->ppl_page, srcs, 0, count, PAGE_SIZE,
|
| 200 | &submit);
|
| 201 |
|
| 202 | return tx;
|
| 203 | }
|
| 204 |
|
| 205 | static void *ppl_io_pool_alloc(gfp_t gfp_mask, void *pool_data)
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| 206 | {
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| 207 | struct kmem_cache *kc = pool_data;
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| 208 | struct ppl_io_unit *io;
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| 209 |
|
| 210 | io = kmem_cache_alloc(kc, gfp_mask);
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| 211 | if (!io)
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| 212 | return NULL;
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| 213 |
|
| 214 | io->header_page = alloc_page(gfp_mask);
|
| 215 | if (!io->header_page) {
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| 216 | kmem_cache_free(kc, io);
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| 217 | return NULL;
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| 218 | }
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| 219 |
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| 220 | return io;
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| 221 | }
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| 222 |
|
| 223 | static void ppl_io_pool_free(void *element, void *pool_data)
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| 224 | {
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| 225 | struct kmem_cache *kc = pool_data;
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| 226 | struct ppl_io_unit *io = element;
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| 227 |
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| 228 | __free_page(io->header_page);
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| 229 | kmem_cache_free(kc, io);
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| 230 | }
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| 231 |
|
| 232 | static struct ppl_io_unit *ppl_new_iounit(struct ppl_log *log,
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| 233 | struct stripe_head *sh)
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| 234 | {
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| 235 | struct ppl_conf *ppl_conf = log->ppl_conf;
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| 236 | struct ppl_io_unit *io;
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| 237 | struct ppl_header *pplhdr;
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| 238 | struct page *header_page;
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| 239 |
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| 240 | io = mempool_alloc(&ppl_conf->io_pool, GFP_NOWAIT);
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| 241 | if (!io)
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| 242 | return NULL;
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| 243 |
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| 244 | header_page = io->header_page;
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| 245 | memset(io, 0, sizeof(*io));
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| 246 | io->header_page = header_page;
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| 247 |
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| 248 | io->log = log;
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| 249 | INIT_LIST_HEAD(&io->log_sibling);
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| 250 | INIT_LIST_HEAD(&io->stripe_list);
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| 251 | atomic_set(&io->pending_stripes, 0);
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| 252 | atomic_set(&io->pending_flushes, 0);
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| 253 | bio_init(&io->bio, log->rdev->bdev, io->biovec, PPL_IO_INLINE_BVECS,
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| 254 | REQ_OP_WRITE | REQ_FUA);
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| 255 |
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| 256 | pplhdr = page_address(io->header_page);
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| 257 | clear_page(pplhdr);
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| 258 | memset(pplhdr->reserved, 0xff, PPL_HDR_RESERVED);
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| 259 | pplhdr->signature = cpu_to_le32(ppl_conf->signature);
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| 260 |
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| 261 | io->seq = atomic64_inc_return(&ppl_conf->seq);
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| 262 | pplhdr->generation = cpu_to_le64(io->seq);
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| 263 |
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| 264 | return io;
|
| 265 | }
|
| 266 |
|
| 267 | static int ppl_log_stripe(struct ppl_log *log, struct stripe_head *sh)
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| 268 | {
|
| 269 | struct ppl_io_unit *io = log->current_io;
|
| 270 | struct ppl_header_entry *e = NULL;
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| 271 | struct ppl_header *pplhdr;
|
| 272 | int i;
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| 273 | sector_t data_sector = 0;
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| 274 | int data_disks = 0;
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| 275 | struct r5conf *conf = sh->raid_conf;
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| 276 |
|
| 277 | pr_debug("%s: stripe: %llu\n", __func__, (unsigned long long)sh->sector);
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| 278 |
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| 279 |
|
| 280 | if (io && (io->pp_size == log->entry_space ||
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| 281 | io->entries_count == PPL_HDR_MAX_ENTRIES)) {
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| 282 | pr_debug("%s: add io_unit blocked by seq: %llu\n",
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| 283 | __func__, io->seq);
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| 284 | io = NULL;
|
| 285 | }
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| 286 |
|
| 287 |
|
| 288 | if (!io) {
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| 289 | io = ppl_new_iounit(log, sh);
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| 290 | if (!io)
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| 291 | return -ENOMEM;
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| 292 | spin_lock_irq(&log->io_list_lock);
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| 293 | list_add_tail(&io->log_sibling, &log->io_list);
|
| 294 | spin_unlock_irq(&log->io_list_lock);
|
| 295 |
|
| 296 | log->current_io = io;
|
| 297 | }
|
| 298 |
|
| 299 | for (i = 0; i < sh->disks; i++) {
|
| 300 | struct r5dev *dev = &sh->dev[i];
|
| 301 |
|
| 302 | if (i != sh->pd_idx && test_bit(R5_Wantwrite, &dev->flags)) {
|
| 303 | if (!data_disks || dev->sector < data_sector)
|
| 304 | data_sector = dev->sector;
|
| 305 | data_disks++;
|
| 306 | }
|
| 307 | }
|
| 308 | BUG_ON(!data_disks);
|
| 309 |
|
| 310 | pr_debug("%s: seq: %llu data_sector: %llu data_disks: %d\n", __func__,
|
| 311 | io->seq, (unsigned long long)data_sector, data_disks);
|
| 312 |
|
| 313 | pplhdr = page_address(io->header_page);
|
| 314 |
|
| 315 | if (io->entries_count > 0) {
|
| 316 | struct ppl_header_entry *last =
|
| 317 | &pplhdr->entries[io->entries_count - 1];
|
| 318 | struct stripe_head *sh_last = list_last_entry(
|
| 319 | &io->stripe_list, struct stripe_head, log_list);
|
| 320 | u64 data_sector_last = le64_to_cpu(last->data_sector);
|
| 321 | u32 data_size_last = le32_to_cpu(last->data_size);
|
| 322 |
|
| 323 | |
| 324 | * Check if we can append the stripe to the last entry. It must
|
| 325 | * be just after the last logged stripe and write to the same
|
| 326 | * disks. Use bit shift and logarithm to avoid 64-bit division.
|
| 327 |
|
| 328 | if ((sh->sector == sh_last->sector + RAID5_STRIPE_SECTORS(conf)) &&
|
| 329 | (data_sector >> ilog2(conf->chunk_sectors) ==
|
| 330 | data_sector_last >> ilog2(conf->chunk_sectors)) &&
|
| 331 | ((data_sector - data_sector_last) * data_disks ==
|
| 332 | data_size_last >> 9))
|
| 333 | e = last;
|
| 334 | }
|
| 335 |
|
| 336 | if (!e) {
|
| 337 | e = &pplhdr->entries[io->entries_count++];
|
| 338 | e->data_sector = cpu_to_le64(data_sector);
|
| 339 | e->parity_disk = cpu_to_le32(sh->pd_idx);
|
| 340 | e->checksum = cpu_to_le32(~0);
|
| 341 | }
|
| 342 |
|
| 343 | le32_add_cpu(&e->data_size, data_disks << PAGE_SHIFT);
|
| 344 |
|
| 345 |
|
| 346 | if (!test_bit(STRIPE_FULL_WRITE, &sh->state)) {
|
| 347 | le32_add_cpu(&e->pp_size, PAGE_SIZE);
|
| 348 | io->pp_size += PAGE_SIZE;
|
| 349 | e->checksum = cpu_to_le32(crc32c(le32_to_cpu(e->checksum),
|
| 350 | page_address(sh->ppl_page),
|
| 351 | PAGE_SIZE));
|
| 352 | }
|
| 353 |
|
| 354 | list_add_tail(&sh->log_list, &io->stripe_list);
|
| 355 | atomic_inc(&io->pending_stripes);
|
| 356 | sh->ppl_io = io;
|
| 357 |
|
| 358 | return 0;
|
| 359 | }
|
| 360 |
|
| 361 | int ppl_write_stripe(struct r5conf *conf, struct stripe_head *sh)
|
| 362 | {
|
| 363 | struct ppl_conf *ppl_conf = conf->log_private;
|
| 364 | struct ppl_io_unit *io = sh->ppl_io;
|
| 365 | struct ppl_log *log;
|
| 366 |
|
| 367 | if (io || test_bit(STRIPE_SYNCING, &sh->state) || !sh->ppl_page ||
|
| 368 | !test_bit(R5_Wantwrite, &sh->dev[sh->pd_idx].flags) ||
|
| 369 | !test_bit(R5_Insync, &sh->dev[sh->pd_idx].flags)) {
|
| 370 | clear_bit(STRIPE_LOG_TRAPPED, &sh->state);
|
| 371 | return -EAGAIN;
|
| 372 | }
|
| 373 |
|
| 374 | log = &ppl_conf->child_logs[sh->pd_idx];
|
| 375 |
|
| 376 | mutex_lock(&log->io_mutex);
|
| 377 |
|
| 378 | if (!log->rdev || test_bit(Faulty, &log->rdev->flags)) {
|
| 379 | mutex_unlock(&log->io_mutex);
|
| 380 | return -EAGAIN;
|
| 381 | }
|
| 382 |
|
| 383 | set_bit(STRIPE_LOG_TRAPPED, &sh->state);
|
| 384 | clear_bit(STRIPE_DELAYED, &sh->state);
|
| 385 | atomic_inc(&sh->count);
|
| 386 |
|
| 387 | if (ppl_log_stripe(log, sh)) {
|
| 388 | spin_lock_irq(&ppl_conf->no_mem_stripes_lock);
|
| 389 | list_add_tail(&sh->log_list, &ppl_conf->no_mem_stripes);
|
| 390 | spin_unlock_irq(&ppl_conf->no_mem_stripes_lock);
|
| 391 | }
|
| 392 |
|
| 393 | mutex_unlock(&log->io_mutex);
|
| 394 |
|
| 395 | return 0;
|
| 396 | }
|
| 397 |
|
| 398 | static void ppl_log_endio(struct bio *bio)
|
| 399 | {
|
| 400 | struct ppl_io_unit *io = bio->bi_private;
|
| 401 | struct ppl_log *log = io->log;
|
| 402 | struct ppl_conf *ppl_conf = log->ppl_conf;
|
| 403 | struct stripe_head *sh, *next;
|
| 404 |
|
| 405 | pr_debug("%s: seq: %llu\n", __func__, io->seq);
|
| 406 |
|
| 407 | if (bio->bi_status)
|
| 408 | md_error(ppl_conf->mddev, log->rdev);
|
| 409 |
|
| 410 | list_for_each_entry_safe(sh, next, &io->stripe_list, log_list) {
|
| 411 | list_del_init(&sh->log_list);
|
| 412 |
|
| 413 | set_bit(STRIPE_HANDLE, &sh->state);
|
| 414 | raid5_release_stripe(sh);
|
| 415 | }
|
| 416 | }
|
| 417 |
|
| 418 | static void ppl_submit_iounit_bio(struct ppl_io_unit *io, struct bio *bio)
|
| 419 | {
|
| 420 | pr_debug("%s: seq: %llu size: %u sector: %llu dev: %pg\n",
|
| 421 | __func__, io->seq, bio->bi_iter.bi_size,
|
| 422 | (unsigned long long)bio->bi_iter.bi_sector,
|
| 423 | bio->bi_bdev);
|
| 424 |
|
| 425 | submit_bio(bio);
|
| 426 | }
|
| 427 |
|
| 428 | static void ppl_submit_iounit(struct ppl_io_unit *io)
|
| 429 | {
|
| 430 | struct ppl_log *log = io->log;
|
| 431 | struct ppl_conf *ppl_conf = log->ppl_conf;
|
| 432 | struct ppl_header *pplhdr = page_address(io->header_page);
|
| 433 | struct bio *bio = &io->bio;
|
| 434 | struct stripe_head *sh;
|
| 435 | int i;
|
| 436 |
|
| 437 | bio->bi_private = io;
|
| 438 |
|
| 439 | if (!log->rdev || test_bit(Faulty, &log->rdev->flags)) {
|
| 440 | ppl_log_endio(bio);
|
| 441 | return;
|
| 442 | }
|
| 443 |
|
| 444 | for (i = 0; i < io->entries_count; i++) {
|
| 445 | struct ppl_header_entry *e = &pplhdr->entries[i];
|
| 446 |
|
| 447 | pr_debug("%s: seq: %llu entry: %d data_sector: %llu pp_size: %u data_size: %u\n",
|
| 448 | __func__, io->seq, i, le64_to_cpu(e->data_sector),
|
| 449 | le32_to_cpu(e->pp_size), le32_to_cpu(e->data_size));
|
| 450 |
|
| 451 | e->data_sector = cpu_to_le64(le64_to_cpu(e->data_sector) >>
|
| 452 | ilog2(ppl_conf->block_size >> 9));
|
| 453 | e->checksum = cpu_to_le32(~le32_to_cpu(e->checksum));
|
| 454 | }
|
| 455 |
|
| 456 | pplhdr->entries_count = cpu_to_le32(io->entries_count);
|
| 457 | pplhdr->checksum = cpu_to_le32(~crc32c(~0, pplhdr, PPL_HEADER_SIZE));
|
| 458 |
|
| 459 |
|
| 460 | if (log->use_multippl &&
|
| 461 | log->rdev->ppl.sector + log->rdev->ppl.size - log->next_io_sector <
|
| 462 | (PPL_HEADER_SIZE + io->pp_size) >> 9)
|
| 463 | log->next_io_sector = log->rdev->ppl.sector;
|
| 464 |
|
| 465 |
|
| 466 | bio->bi_end_io = ppl_log_endio;
|
| 467 | bio->bi_iter.bi_sector = log->next_io_sector;
|
| 468 | __bio_add_page(bio, io->header_page, PAGE_SIZE, 0);
|
| 469 |
|
| 470 | pr_debug("%s: log->current_io_sector: %llu\n", __func__,
|
| 471 | (unsigned long long)log->next_io_sector);
|
| 472 |
|
| 473 | if (log->use_multippl)
|
| 474 | log->next_io_sector += (PPL_HEADER_SIZE + io->pp_size) >> 9;
|
| 475 |
|
| 476 | WARN_ON(log->disk_flush_bitmap != 0);
|
| 477 |
|
| 478 | list_for_each_entry(sh, &io->stripe_list, log_list) {
|
| 479 | for (i = 0; i < sh->disks; i++) {
|
| 480 | struct r5dev *dev = &sh->dev[i];
|
| 481 |
|
| 482 | if ((ppl_conf->child_logs[i].wb_cache_on) &&
|
| 483 | (test_bit(R5_Wantwrite, &dev->flags))) {
|
| 484 | set_bit(i, &log->disk_flush_bitmap);
|
| 485 | }
|
| 486 | }
|
| 487 |
|
| 488 |
|
| 489 | if (test_bit(STRIPE_FULL_WRITE, &sh->state))
|
| 490 | continue;
|
| 491 |
|
| 492 | if (!bio_add_page(bio, sh->ppl_page, PAGE_SIZE, 0)) {
|
| 493 | struct bio *prev = bio;
|
| 494 |
|
| 495 | bio = bio_alloc_bioset(prev->bi_bdev, BIO_MAX_VECS,
|
| 496 | prev->bi_opf, GFP_NOIO,
|
| 497 | &ppl_conf->bs);
|
| 498 | bio->bi_iter.bi_sector = bio_end_sector(prev);
|
| 499 | __bio_add_page(bio, sh->ppl_page, PAGE_SIZE, 0);
|
| 500 |
|
| 501 | bio_chain(bio, prev);
|
| 502 | ppl_submit_iounit_bio(io, prev);
|
| 503 | }
|
| 504 | }
|
| 505 |
|
| 506 | ppl_submit_iounit_bio(io, bio);
|
| 507 | }
|
| 508 |
|
| 509 | static void ppl_submit_current_io(struct ppl_log *log)
|
| 510 | {
|
| 511 | struct ppl_io_unit *io;
|
| 512 |
|
| 513 | spin_lock_irq(&log->io_list_lock);
|
| 514 |
|
| 515 | io = list_first_entry_or_null(&log->io_list, struct ppl_io_unit,
|
| 516 | log_sibling);
|
| 517 | if (io && io->submitted)
|
| 518 | io = NULL;
|
| 519 |
|
| 520 | spin_unlock_irq(&log->io_list_lock);
|
| 521 |
|
| 522 | if (io) {
|
| 523 | io->submitted = true;
|
| 524 |
|
| 525 | if (io == log->current_io)
|
| 526 | log->current_io = NULL;
|
| 527 |
|
| 528 | ppl_submit_iounit(io);
|
| 529 | }
|
| 530 | }
|
| 531 |
|
| 532 | void ppl_write_stripe_run(struct r5conf *conf)
|
| 533 | {
|
| 534 | struct ppl_conf *ppl_conf = conf->log_private;
|
| 535 | struct ppl_log *log;
|
| 536 | int i;
|
| 537 |
|
| 538 | for (i = 0; i < ppl_conf->count; i++) {
|
| 539 | log = &ppl_conf->child_logs[i];
|
| 540 |
|
| 541 | mutex_lock(&log->io_mutex);
|
| 542 | ppl_submit_current_io(log);
|
| 543 | mutex_unlock(&log->io_mutex);
|
| 544 | }
|
| 545 | }
|
| 546 |
|
| 547 | static void ppl_io_unit_finished(struct ppl_io_unit *io)
|
| 548 | {
|
| 549 | struct ppl_log *log = io->log;
|
| 550 | struct ppl_conf *ppl_conf = log->ppl_conf;
|
| 551 | struct r5conf *conf = ppl_conf->mddev->private;
|
| 552 | unsigned long flags;
|
| 553 |
|
| 554 | pr_debug("%s: seq: %llu\n", __func__, io->seq);
|
| 555 |
|
| 556 | local_irq_save(flags);
|
| 557 |
|
| 558 | spin_lock(&log->io_list_lock);
|
| 559 | list_del(&io->log_sibling);
|
| 560 | spin_unlock(&log->io_list_lock);
|
| 561 |
|
| 562 | mempool_free(io, &ppl_conf->io_pool);
|
| 563 |
|
| 564 | spin_lock(&ppl_conf->no_mem_stripes_lock);
|
| 565 | if (!list_empty(&ppl_conf->no_mem_stripes)) {
|
| 566 | struct stripe_head *sh;
|
| 567 |
|
| 568 | sh = list_first_entry(&ppl_conf->no_mem_stripes,
|
| 569 | struct stripe_head, log_list);
|
| 570 | list_del_init(&sh->log_list);
|
| 571 | set_bit(STRIPE_HANDLE, &sh->state);
|
| 572 | raid5_release_stripe(sh);
|
| 573 | }
|
| 574 | spin_unlock(&ppl_conf->no_mem_stripes_lock);
|
| 575 |
|
| 576 | local_irq_restore(flags);
|
| 577 |
|
| 578 | wake_up(&conf->wait_for_quiescent);
|
| 579 | }
|
| 580 |
|
| 581 | static void ppl_flush_endio(struct bio *bio)
|
| 582 | {
|
| 583 | struct ppl_io_unit *io = bio->bi_private;
|
| 584 | struct ppl_log *log = io->log;
|
| 585 | struct ppl_conf *ppl_conf = log->ppl_conf;
|
| 586 | struct r5conf *conf = ppl_conf->mddev->private;
|
| 587 |
|
| 588 | pr_debug("%s: dev: %pg\n", __func__, bio->bi_bdev);
|
| 589 |
|
| 590 | if (bio->bi_status) {
|
| 591 | struct md_rdev *rdev;
|
| 592 |
|
| 593 | rcu_read_lock();
|
| 594 | rdev = md_find_rdev_rcu(conf->mddev, bio_dev(bio));
|
| 595 | if (rdev)
|
| 596 | md_error(rdev->mddev, rdev);
|
| 597 | rcu_read_unlock();
|
| 598 | }
|
| 599 |
|
| 600 | bio_put(bio);
|
| 601 |
|
| 602 | if (atomic_dec_and_test(&io->pending_flushes)) {
|
| 603 | ppl_io_unit_finished(io);
|
| 604 | md_wakeup_thread(conf->mddev->thread);
|
| 605 | }
|
| 606 | }
|
| 607 |
|
| 608 | static void ppl_do_flush(struct ppl_io_unit *io)
|
| 609 | {
|
| 610 | struct ppl_log *log = io->log;
|
| 611 | struct ppl_conf *ppl_conf = log->ppl_conf;
|
| 612 | struct r5conf *conf = ppl_conf->mddev->private;
|
| 613 | int raid_disks = conf->raid_disks;
|
| 614 | int flushed_disks = 0;
|
| 615 | int i;
|
| 616 |
|
| 617 | atomic_set(&io->pending_flushes, raid_disks);
|
| 618 |
|
| 619 | for_each_set_bit(i, &log->disk_flush_bitmap, raid_disks) {
|
| 620 | struct md_rdev *rdev;
|
| 621 | struct block_device *bdev = NULL;
|
| 622 |
|
| 623 | rdev = conf->disks[i].rdev;
|
| 624 | if (rdev && !test_bit(Faulty, &rdev->flags))
|
| 625 | bdev = rdev->bdev;
|
| 626 |
|
| 627 | if (bdev) {
|
| 628 | struct bio *bio;
|
| 629 |
|
| 630 | bio = bio_alloc_bioset(bdev, 0,
|
| 631 | REQ_OP_WRITE | REQ_PREFLUSH,
|
| 632 | GFP_NOIO, &ppl_conf->flush_bs);
|
| 633 | bio->bi_private = io;
|
| 634 | bio->bi_end_io = ppl_flush_endio;
|
| 635 |
|
| 636 | pr_debug("%s: dev: %ps\n", __func__, bio->bi_bdev);
|
| 637 |
|
| 638 | submit_bio(bio);
|
| 639 | flushed_disks++;
|
| 640 | }
|
| 641 | }
|
| 642 |
|
| 643 | log->disk_flush_bitmap = 0;
|
| 644 |
|
| 645 | for (i = flushed_disks ; i < raid_disks; i++) {
|
| 646 | if (atomic_dec_and_test(&io->pending_flushes)) {
|
| 647 | ppl_io_unit_finished(io);
|
| 648 | break;
|
| 649 | }
|
| 650 | }
|
| 651 | }
|
| 652 |
|
| 653 | static inline bool ppl_no_io_unit_submitted(struct r5conf *conf,
|
| 654 | struct ppl_log *log)
|
| 655 | {
|
| 656 | struct ppl_io_unit *io;
|
| 657 |
|
| 658 | io = list_first_entry_or_null(&log->io_list, struct ppl_io_unit,
|
| 659 | log_sibling);
|
| 660 |
|
| 661 | return !io || !io->submitted;
|
| 662 | }
|
| 663 |
|
| 664 | void ppl_quiesce(struct r5conf *conf, int quiesce)
|
| 665 | {
|
| 666 | struct ppl_conf *ppl_conf = conf->log_private;
|
| 667 | int i;
|
| 668 |
|
| 669 | if (quiesce) {
|
| 670 | for (i = 0; i < ppl_conf->count; i++) {
|
| 671 | struct ppl_log *log = &ppl_conf->child_logs[i];
|
| 672 |
|
| 673 | spin_lock_irq(&log->io_list_lock);
|
| 674 | wait_event_lock_irq(conf->wait_for_quiescent,
|
| 675 | ppl_no_io_unit_submitted(conf, log),
|
| 676 | log->io_list_lock);
|
| 677 | spin_unlock_irq(&log->io_list_lock);
|
| 678 | }
|
| 679 | }
|
| 680 | }
|
| 681 |
|
| 682 | int ppl_handle_flush_request(struct bio *bio)
|
| 683 | {
|
| 684 | if (bio->bi_iter.bi_size == 0) {
|
| 685 | bio_endio(bio);
|
| 686 | return 0;
|
| 687 | }
|
| 688 | bio->bi_opf &= ~REQ_PREFLUSH;
|
| 689 | return -EAGAIN;
|
| 690 | }
|
| 691 |
|
| 692 | void ppl_stripe_write_finished(struct stripe_head *sh)
|
| 693 | {
|
| 694 | struct ppl_io_unit *io;
|
| 695 |
|
| 696 | io = sh->ppl_io;
|
| 697 | sh->ppl_io = NULL;
|
| 698 |
|
| 699 | if (io && atomic_dec_and_test(&io->pending_stripes)) {
|
| 700 | if (io->log->disk_flush_bitmap)
|
| 701 | ppl_do_flush(io);
|
| 702 | else
|
| 703 | ppl_io_unit_finished(io);
|
| 704 | }
|
| 705 | }
|
| 706 |
|
| 707 | static void ppl_xor(int size, struct page *page1, struct page *page2)
|
| 708 | {
|
| 709 | struct async_submit_ctl submit;
|
| 710 | struct dma_async_tx_descriptor *tx;
|
| 711 | struct page *xor_srcs[] = { page1, page2 };
|
| 712 |
|
| 713 | init_async_submit(&submit, ASYNC_TX_ACK|ASYNC_TX_XOR_DROP_DST,
|
| 714 | NULL, NULL, NULL, NULL);
|
| 715 | tx = async_xor(page1, xor_srcs, 0, 2, size, &submit);
|
| 716 |
|
| 717 | async_tx_quiesce(&tx);
|
| 718 | }
|
| 719 |
|
| 720 | |
| 721 | * PPL recovery strategy: xor partial parity and data from all modified data
|
| 722 | * disks within a stripe and write the result as the new stripe parity. If all
|
| 723 | * stripe data disks are modified (full stripe write), no partial parity is
|
| 724 | * available, so just xor the data disks.
|
| 725 | *
|
| 726 | * Recovery of a PPL entry shall occur only if all modified data disks are
|
| 727 | * available and read from all of them succeeds.
|
| 728 | *
|
| 729 | * A PPL entry applies to a stripe, partial parity size for an entry is at most
|
| 730 | * the size of the chunk. Examples of possible cases for a single entry:
|
| 731 | *
|
| 732 | * case 0: single data disk write:
|
| 733 | * data0 data1 data2 ppl parity
|
| 734 | * +--------+--------+--------+ +--------------------+
|
| 735 | * | ------ | ------ | ------ | +----+ | (no change) |
|
| 736 | * | ------ | -data- | ------ | | pp | -> | data1 ^ pp |
|
| 737 | * | ------ | -data- | ------ | | pp | -> | data1 ^ pp |
|
| 738 | * | ------ | ------ | ------ | +----+ | (no change) |
|
| 739 | * +--------+--------+--------+ +--------------------+
|
| 740 | * pp_size = data_size
|
| 741 | *
|
| 742 | * case 1: more than one data disk write:
|
| 743 | * data0 data1 data2 ppl parity
|
| 744 | * +--------+--------+--------+ +--------------------+
|
| 745 | * | ------ | ------ | ------ | +----+ | (no change) |
|
| 746 | * | -data- | -data- | ------ | | pp | -> | data0 ^ data1 ^ pp |
|
| 747 | * | -data- | -data- | ------ | | pp | -> | data0 ^ data1 ^ pp |
|
| 748 | * | ------ | ------ | ------ | +----+ | (no change) |
|
| 749 | * +--------+--------+--------+ +--------------------+
|
| 750 | * pp_size = data_size / modified_data_disks
|
| 751 | *
|
| 752 | * case 2: write to all data disks (also full stripe write):
|
| 753 | * data0 data1 data2 parity
|
| 754 | * +--------+--------+--------+ +--------------------+
|
| 755 | * | ------ | ------ | ------ | | (no change) |
|
| 756 | * | -data- | -data- | -data- | --------> | xor all data |
|
| 757 | * | ------ | ------ | ------ | --------> | (no change) |
|
| 758 | * | ------ | ------ | ------ | | (no change) |
|
| 759 | * +--------+--------+--------+ +--------------------+
|
| 760 | * pp_size = 0
|
| 761 | *
|
| 762 | * The following cases are possible only in other implementations. The recovery
|
| 763 | * code can handle them, but they are not generated at runtime because they can
|
| 764 | * be reduced to cases 0, 1 and 2:
|
| 765 | *
|
| 766 | * case 3:
|
| 767 | * data0 data1 data2 ppl parity
|
| 768 | * +--------+--------+--------+ +----+ +--------------------+
|
| 769 | * | ------ | -data- | -data- | | pp | | data1 ^ data2 ^ pp |
|
| 770 | * | ------ | -data- | -data- | | pp | -> | data1 ^ data2 ^ pp |
|
| 771 | * | -data- | -data- | -data- | | -- | -> | xor all data |
|
| 772 | * | -data- | -data- | ------ | | pp | | data0 ^ data1 ^ pp |
|
| 773 | * +--------+--------+--------+ +----+ +--------------------+
|
| 774 | * pp_size = chunk_size
|
| 775 | *
|
| 776 | * case 4:
|
| 777 | * data0 data1 data2 ppl parity
|
| 778 | * +--------+--------+--------+ +----+ +--------------------+
|
| 779 | * | ------ | -data- | ------ | | pp | | data1 ^ pp |
|
| 780 | * | ------ | ------ | ------ | | -- | -> | (no change) |
|
| 781 | * | ------ | ------ | ------ | | -- | -> | (no change) |
|
| 782 | * | -data- | ------ | ------ | | pp | | data0 ^ pp |
|
| 783 | * +--------+--------+--------+ +----+ +--------------------+
|
| 784 | * pp_size = chunk_size
|
| 785 |
|
| 786 | static int ppl_recover_entry(struct ppl_log *log, struct ppl_header_entry *e,
|
| 787 | sector_t ppl_sector)
|
| 788 | {
|
| 789 | struct ppl_conf *ppl_conf = log->ppl_conf;
|
| 790 | struct mddev *mddev = ppl_conf->mddev;
|
| 791 | struct r5conf *conf = mddev->private;
|
| 792 | int block_size = ppl_conf->block_size;
|
| 793 | struct page *page1;
|
| 794 | struct page *page2;
|
| 795 | sector_t r_sector_first;
|
| 796 | sector_t r_sector_last;
|
| 797 | int strip_sectors;
|
| 798 | int data_disks;
|
| 799 | int i;
|
| 800 | int ret = 0;
|
| 801 | unsigned int pp_size = le32_to_cpu(e->pp_size);
|
| 802 | unsigned int data_size = le32_to_cpu(e->data_size);
|
| 803 |
|
| 804 | page1 = alloc_page(GFP_KERNEL);
|
| 805 | page2 = alloc_page(GFP_KERNEL);
|
| 806 |
|
| 807 | if (!page1 || !page2) {
|
| 808 | ret = -ENOMEM;
|
| 809 | goto out;
|
| 810 | }
|
| 811 |
|
| 812 | r_sector_first = le64_to_cpu(e->data_sector) * (block_size >> 9);
|
| 813 |
|
| 814 | if ((pp_size >> 9) < conf->chunk_sectors) {
|
| 815 | if (pp_size > 0) {
|
| 816 | data_disks = data_size / pp_size;
|
| 817 | strip_sectors = pp_size >> 9;
|
| 818 | } else {
|
| 819 | data_disks = conf->raid_disks - conf->max_degraded;
|
| 820 | strip_sectors = (data_size >> 9) / data_disks;
|
| 821 | }
|
| 822 | r_sector_last = r_sector_first +
|
| 823 | (data_disks - 1) * conf->chunk_sectors +
|
| 824 | strip_sectors;
|
| 825 | } else {
|
| 826 | data_disks = conf->raid_disks - conf->max_degraded;
|
| 827 | strip_sectors = conf->chunk_sectors;
|
| 828 | r_sector_last = r_sector_first + (data_size >> 9);
|
| 829 | }
|
| 830 |
|
| 831 | pr_debug("%s: array sector first: %llu last: %llu\n", __func__,
|
| 832 | (unsigned long long)r_sector_first,
|
| 833 | (unsigned long long)r_sector_last);
|
| 834 |
|
| 835 |
|
| 836 | if (block_size == 512 &&
|
| 837 | (r_sector_first & (RAID5_STRIPE_SECTORS(conf) - 1)) == 0 &&
|
| 838 | (r_sector_last & (RAID5_STRIPE_SECTORS(conf) - 1)) == 0)
|
| 839 | block_size = RAID5_STRIPE_SIZE(conf);
|
| 840 |
|
| 841 |
|
| 842 | for (i = 0; i < strip_sectors; i += (block_size >> 9)) {
|
| 843 | bool update_parity = false;
|
| 844 | sector_t parity_sector;
|
| 845 | struct md_rdev *parity_rdev;
|
| 846 | struct stripe_head sh;
|
| 847 | int disk;
|
| 848 | int indent = 0;
|
| 849 |
|
| 850 | pr_debug("%s:%*s iter %d start\n", __func__, indent, "", i);
|
| 851 | indent += 2;
|
| 852 |
|
| 853 | memset(page_address(page1), 0, PAGE_SIZE);
|
| 854 |
|
| 855 |
|
| 856 | for (disk = 0; disk < data_disks; disk++) {
|
| 857 | int dd_idx;
|
| 858 | struct md_rdev *rdev;
|
| 859 | sector_t sector;
|
| 860 | sector_t r_sector = r_sector_first + i +
|
| 861 | (disk * conf->chunk_sectors);
|
| 862 |
|
| 863 | pr_debug("%s:%*s data member disk %d start\n",
|
| 864 | __func__, indent, "", disk);
|
| 865 | indent += 2;
|
| 866 |
|
| 867 | if (r_sector >= r_sector_last) {
|
| 868 | pr_debug("%s:%*s array sector %llu doesn't need parity update\n",
|
| 869 | __func__, indent, "",
|
| 870 | (unsigned long long)r_sector);
|
| 871 | indent -= 2;
|
| 872 | continue;
|
| 873 | }
|
| 874 |
|
| 875 | update_parity = true;
|
| 876 |
|
| 877 |
|
| 878 | sector = raid5_compute_sector(conf, r_sector, 0,
|
| 879 | &dd_idx, NULL);
|
| 880 | pr_debug("%s:%*s processing array sector %llu => data member disk %d, sector %llu\n",
|
| 881 | __func__, indent, "",
|
| 882 | (unsigned long long)r_sector, dd_idx,
|
| 883 | (unsigned long long)sector);
|
| 884 |
|
| 885 | rdev = conf->disks[dd_idx].rdev;
|
| 886 | if (!rdev || (!test_bit(In_sync, &rdev->flags) &&
|
| 887 | sector >= rdev->recovery_offset)) {
|
| 888 | pr_debug("%s:%*s data member disk %d missing\n",
|
| 889 | __func__, indent, "", dd_idx);
|
| 890 | update_parity = false;
|
| 891 | break;
|
| 892 | }
|
| 893 |
|
| 894 | pr_debug("%s:%*s reading data member disk %pg sector %llu\n",
|
| 895 | __func__, indent, "", rdev->bdev,
|
| 896 | (unsigned long long)sector);
|
| 897 | if (!sync_page_io(rdev, sector, block_size, page2,
|
| 898 | REQ_OP_READ, false)) {
|
| 899 | md_error(mddev, rdev);
|
| 900 | pr_debug("%s:%*s read failed!\n", __func__,
|
| 901 | indent, "");
|
| 902 | ret = -EIO;
|
| 903 | goto out;
|
| 904 | }
|
| 905 |
|
| 906 | ppl_xor(block_size, page1, page2);
|
| 907 |
|
| 908 | indent -= 2;
|
| 909 | }
|
| 910 |
|
| 911 | if (!update_parity)
|
| 912 | continue;
|
| 913 |
|
| 914 | if (pp_size > 0) {
|
| 915 | pr_debug("%s:%*s reading pp disk sector %llu\n",
|
| 916 | __func__, indent, "",
|
| 917 | (unsigned long long)(ppl_sector + i));
|
| 918 | if (!sync_page_io(log->rdev,
|
| 919 | ppl_sector - log->rdev->data_offset + i,
|
| 920 | block_size, page2, REQ_OP_READ,
|
| 921 | false)) {
|
| 922 | pr_debug("%s:%*s read failed!\n", __func__,
|
| 923 | indent, "");
|
| 924 | md_error(mddev, log->rdev);
|
| 925 | ret = -EIO;
|
| 926 | goto out;
|
| 927 | }
|
| 928 |
|
| 929 | ppl_xor(block_size, page1, page2);
|
| 930 | }
|
| 931 |
|
| 932 |
|
| 933 | parity_sector = raid5_compute_sector(conf, r_sector_first + i,
|
| 934 | 0, &disk, &sh);
|
| 935 | BUG_ON(sh.pd_idx != le32_to_cpu(e->parity_disk));
|
| 936 |
|
| 937 | parity_rdev = conf->disks[sh.pd_idx].rdev;
|
| 938 |
|
| 939 | BUG_ON(parity_rdev->bdev->bd_dev != log->rdev->bdev->bd_dev);
|
| 940 | pr_debug("%s:%*s write parity at sector %llu, disk %pg\n",
|
| 941 | __func__, indent, "",
|
| 942 | (unsigned long long)parity_sector,
|
| 943 | parity_rdev->bdev);
|
| 944 | if (!sync_page_io(parity_rdev, parity_sector, block_size,
|
| 945 | page1, REQ_OP_WRITE, false)) {
|
| 946 | pr_debug("%s:%*s parity write error!\n", __func__,
|
| 947 | indent, "");
|
| 948 | md_error(mddev, parity_rdev);
|
| 949 | ret = -EIO;
|
| 950 | goto out;
|
| 951 | }
|
| 952 | }
|
| 953 | out:
|
| 954 | if (page1)
|
| 955 | __free_page(page1);
|
| 956 | if (page2)
|
| 957 | __free_page(page2);
|
| 958 | return ret;
|
| 959 | }
|
| 960 |
|
| 961 | static int ppl_recover(struct ppl_log *log, struct ppl_header *pplhdr,
|
| 962 | sector_t offset)
|
| 963 | {
|
| 964 | struct ppl_conf *ppl_conf = log->ppl_conf;
|
| 965 | struct md_rdev *rdev = log->rdev;
|
| 966 | struct mddev *mddev = rdev->mddev;
|
| 967 | sector_t ppl_sector = rdev->ppl.sector + offset +
|
| 968 | (PPL_HEADER_SIZE >> 9);
|
| 969 | struct page *page;
|
| 970 | int i;
|
| 971 | int ret = 0;
|
| 972 |
|
| 973 | page = alloc_page(GFP_KERNEL);
|
| 974 | if (!page)
|
| 975 | return -ENOMEM;
|
| 976 |
|
| 977 |
|
| 978 | for (i = 0; i < le32_to_cpu(pplhdr->entries_count); i++) {
|
| 979 | struct ppl_header_entry *e = &pplhdr->entries[i];
|
| 980 | u32 pp_size = le32_to_cpu(e->pp_size);
|
| 981 | sector_t sector = ppl_sector;
|
| 982 | int ppl_entry_sectors = pp_size >> 9;
|
| 983 | u32 crc, crc_stored;
|
| 984 |
|
| 985 | pr_debug("%s: disk: %d entry: %d ppl_sector: %llu pp_size: %u\n",
|
| 986 | __func__, rdev->raid_disk, i,
|
| 987 | (unsigned long long)ppl_sector, pp_size);
|
| 988 |
|
| 989 | crc = ~0;
|
| 990 | crc_stored = le32_to_cpu(e->checksum);
|
| 991 |
|
| 992 |
|
| 993 | while (pp_size) {
|
| 994 | int s = pp_size > PAGE_SIZE ? PAGE_SIZE : pp_size;
|
| 995 |
|
| 996 | if (!sync_page_io(rdev, sector - rdev->data_offset,
|
| 997 | s, page, REQ_OP_READ, false)) {
|
| 998 | md_error(mddev, rdev);
|
| 999 | ret = -EIO;
|
| 1000 | goto out;
|
| 1001 | }
|
| 1002 |
|
| 1003 | crc = crc32c(crc, page_address(page), s);
|
| 1004 |
|
| 1005 | pp_size -= s;
|
| 1006 | sector += s >> 9;
|
| 1007 | }
|
| 1008 |
|
| 1009 | crc = ~crc;
|
| 1010 |
|
| 1011 | if (crc != crc_stored) {
|
| 1012 | |
| 1013 | * Don't recover this entry if the checksum does not
|
| 1014 | * match, but keep going and try to recover other
|
| 1015 | * entries.
|
| 1016 |
|
| 1017 | pr_debug("%s: ppl entry crc does not match: stored: 0x%x calculated: 0x%x\n",
|
| 1018 | __func__, crc_stored, crc);
|
| 1019 | ppl_conf->mismatch_count++;
|
| 1020 | } else {
|
| 1021 | ret = ppl_recover_entry(log, e, ppl_sector);
|
| 1022 | if (ret)
|
| 1023 | goto out;
|
| 1024 | ppl_conf->recovered_entries++;
|
| 1025 | }
|
| 1026 |
|
| 1027 | ppl_sector += ppl_entry_sectors;
|
| 1028 | }
|
| 1029 |
|
| 1030 |
|
| 1031 | ret = blkdev_issue_flush(rdev->bdev);
|
| 1032 | out:
|
| 1033 | __free_page(page);
|
| 1034 | return ret;
|
| 1035 | }
|
| 1036 |
|
| 1037 | static int ppl_write_empty_header(struct ppl_log *log)
|
| 1038 | {
|
| 1039 | struct page *page;
|
| 1040 | struct ppl_header *pplhdr;
|
| 1041 | struct md_rdev *rdev = log->rdev;
|
| 1042 | int ret = 0;
|
| 1043 |
|
| 1044 | pr_debug("%s: disk: %d ppl_sector: %llu\n", __func__,
|
| 1045 | rdev->raid_disk, (unsigned long long)rdev->ppl.sector);
|
| 1046 |
|
| 1047 | page = alloc_page(GFP_NOIO | __GFP_ZERO);
|
| 1048 | if (!page)
|
| 1049 | return -ENOMEM;
|
| 1050 |
|
| 1051 | pplhdr = page_address(page);
|
| 1052 |
|
| 1053 | blkdev_issue_zeroout(rdev->bdev, rdev->ppl.sector,
|
| 1054 | log->rdev->ppl.size, GFP_NOIO, 0);
|
| 1055 | memset(pplhdr->reserved, 0xff, PPL_HDR_RESERVED);
|
| 1056 | pplhdr->signature = cpu_to_le32(log->ppl_conf->signature);
|
| 1057 | pplhdr->checksum = cpu_to_le32(~crc32c(~0, pplhdr, PAGE_SIZE));
|
| 1058 |
|
| 1059 | if (!sync_page_io(rdev, rdev->ppl.sector - rdev->data_offset,
|
| 1060 | PPL_HEADER_SIZE, page, REQ_OP_WRITE | REQ_SYNC |
|
| 1061 | REQ_FUA, false)) {
|
| 1062 | md_error(rdev->mddev, rdev);
|
| 1063 | ret = -EIO;
|
| 1064 | }
|
| 1065 |
|
| 1066 | __free_page(page);
|
| 1067 | return ret;
|
| 1068 | }
|
| 1069 |
|
| 1070 | static int ppl_load_distributed(struct ppl_log *log)
|
| 1071 | {
|
| 1072 | struct ppl_conf *ppl_conf = log->ppl_conf;
|
| 1073 | struct md_rdev *rdev = log->rdev;
|
| 1074 | struct mddev *mddev = rdev->mddev;
|
| 1075 | struct page *page, *page2;
|
| 1076 | struct ppl_header *pplhdr = NULL, *prev_pplhdr = NULL;
|
| 1077 | u32 crc, crc_stored;
|
| 1078 | u32 signature;
|
| 1079 | int ret = 0, i;
|
| 1080 | sector_t pplhdr_offset = 0, prev_pplhdr_offset = 0;
|
| 1081 |
|
| 1082 | pr_debug("%s: disk: %d\n", __func__, rdev->raid_disk);
|
| 1083 |
|
| 1084 | page = alloc_page(GFP_KERNEL);
|
| 1085 | if (!page)
|
| 1086 | return -ENOMEM;
|
| 1087 |
|
| 1088 | page2 = alloc_page(GFP_KERNEL);
|
| 1089 | if (!page2) {
|
| 1090 | __free_page(page);
|
| 1091 | return -ENOMEM;
|
| 1092 | }
|
| 1093 |
|
| 1094 |
|
| 1095 | while (pplhdr_offset < rdev->ppl.size - (PPL_HEADER_SIZE >> 9)) {
|
| 1096 | if (!sync_page_io(rdev,
|
| 1097 | rdev->ppl.sector - rdev->data_offset +
|
| 1098 | pplhdr_offset, PAGE_SIZE, page, REQ_OP_READ,
|
| 1099 | false)) {
|
| 1100 | md_error(mddev, rdev);
|
| 1101 | ret = -EIO;
|
| 1102 |
|
| 1103 | pplhdr = NULL;
|
| 1104 | break;
|
| 1105 | }
|
| 1106 | pplhdr = page_address(page);
|
| 1107 |
|
| 1108 |
|
| 1109 | crc_stored = le32_to_cpu(pplhdr->checksum);
|
| 1110 | pplhdr->checksum = 0;
|
| 1111 | crc = ~crc32c(~0, pplhdr, PAGE_SIZE);
|
| 1112 |
|
| 1113 | if (crc_stored != crc) {
|
| 1114 | pr_debug("%s: ppl header crc does not match: stored: 0x%x calculated: 0x%x (offset: %llu)\n",
|
| 1115 | __func__, crc_stored, crc,
|
| 1116 | (unsigned long long)pplhdr_offset);
|
| 1117 | pplhdr = prev_pplhdr;
|
| 1118 | pplhdr_offset = prev_pplhdr_offset;
|
| 1119 | break;
|
| 1120 | }
|
| 1121 |
|
| 1122 | signature = le32_to_cpu(pplhdr->signature);
|
| 1123 |
|
| 1124 | if (mddev->external) {
|
| 1125 | |
| 1126 | * For external metadata the header signature is set and
|
| 1127 | * validated in userspace.
|
| 1128 |
|
| 1129 | ppl_conf->signature = signature;
|
| 1130 | } else if (ppl_conf->signature != signature) {
|
| 1131 | pr_debug("%s: ppl header signature does not match: stored: 0x%x configured: 0x%x (offset: %llu)\n",
|
| 1132 | __func__, signature, ppl_conf->signature,
|
| 1133 | (unsigned long long)pplhdr_offset);
|
| 1134 | pplhdr = prev_pplhdr;
|
| 1135 | pplhdr_offset = prev_pplhdr_offset;
|
| 1136 | break;
|
| 1137 | }
|
| 1138 |
|
| 1139 | if (prev_pplhdr && le64_to_cpu(prev_pplhdr->generation) >
|
| 1140 | le64_to_cpu(pplhdr->generation)) {
|
| 1141 |
|
| 1142 | pplhdr = prev_pplhdr;
|
| 1143 | pplhdr_offset = prev_pplhdr_offset;
|
| 1144 | break;
|
| 1145 | }
|
| 1146 |
|
| 1147 | prev_pplhdr_offset = pplhdr_offset;
|
| 1148 | prev_pplhdr = pplhdr;
|
| 1149 |
|
| 1150 | swap(page, page2);
|
| 1151 |
|
| 1152 |
|
| 1153 | for (i = 0; i < le32_to_cpu(pplhdr->entries_count); i++)
|
| 1154 | pplhdr_offset +=
|
| 1155 | le32_to_cpu(pplhdr->entries[i].pp_size) >> 9;
|
| 1156 | pplhdr_offset += PPL_HEADER_SIZE >> 9;
|
| 1157 | }
|
| 1158 |
|
| 1159 |
|
| 1160 | if (!pplhdr)
|
| 1161 | ppl_conf->mismatch_count++;
|
| 1162 | else
|
| 1163 | pr_debug("%s: latest PPL found at offset: %llu, with generation: %llu\n",
|
| 1164 | __func__, (unsigned long long)pplhdr_offset,
|
| 1165 | le64_to_cpu(pplhdr->generation));
|
| 1166 |
|
| 1167 |
|
| 1168 | if (pplhdr && !mddev->pers && mddev->resync_offset != MaxSector)
|
| 1169 | ret = ppl_recover(log, pplhdr, pplhdr_offset);
|
| 1170 |
|
| 1171 |
|
| 1172 | if (!ret && !mddev->pers)
|
| 1173 | ret = ppl_write_empty_header(log);
|
| 1174 |
|
| 1175 | __free_page(page);
|
| 1176 | __free_page(page2);
|
| 1177 |
|
| 1178 | pr_debug("%s: return: %d mismatch_count: %d recovered_entries: %d\n",
|
| 1179 | __func__, ret, ppl_conf->mismatch_count,
|
| 1180 | ppl_conf->recovered_entries);
|
| 1181 | return ret;
|
| 1182 | }
|
| 1183 |
|
| 1184 | static int ppl_load(struct ppl_conf *ppl_conf)
|
| 1185 | {
|
| 1186 | int ret = 0;
|
| 1187 | u32 signature = 0;
|
| 1188 | bool signature_set = false;
|
| 1189 | int i;
|
| 1190 |
|
| 1191 | for (i = 0; i < ppl_conf->count; i++) {
|
| 1192 | struct ppl_log *log = &ppl_conf->child_logs[i];
|
| 1193 |
|
| 1194 |
|
| 1195 | if (!log->rdev)
|
| 1196 | continue;
|
| 1197 |
|
| 1198 | ret = ppl_load_distributed(log);
|
| 1199 | if (ret)
|
| 1200 | break;
|
| 1201 |
|
| 1202 | |
| 1203 | * For external metadata we can't check if the signature is
|
| 1204 | * correct on a single drive, but we can check if it is the same
|
| 1205 | * on all drives.
|
| 1206 |
|
| 1207 | if (ppl_conf->mddev->external) {
|
| 1208 | if (!signature_set) {
|
| 1209 | signature = ppl_conf->signature;
|
| 1210 | signature_set = true;
|
| 1211 | } else if (signature != ppl_conf->signature) {
|
| 1212 | pr_warn("md/raid:%s: PPL header signature does not match on all member drives\n",
|
| 1213 | mdname(ppl_conf->mddev));
|
| 1214 | ret = -EINVAL;
|
| 1215 | break;
|
| 1216 | }
|
| 1217 | }
|
| 1218 | }
|
| 1219 |
|
| 1220 | pr_debug("%s: return: %d mismatch_count: %d recovered_entries: %d\n",
|
| 1221 | __func__, ret, ppl_conf->mismatch_count,
|
| 1222 | ppl_conf->recovered_entries);
|
| 1223 | return ret;
|
| 1224 | }
|
| 1225 |
|
| 1226 | static void __ppl_exit_log(struct ppl_conf *ppl_conf)
|
| 1227 | {
|
| 1228 | clear_bit(MD_HAS_PPL, &ppl_conf->mddev->flags);
|
| 1229 | clear_bit(MD_HAS_MULTIPLE_PPLS, &ppl_conf->mddev->flags);
|
| 1230 |
|
| 1231 | kfree(ppl_conf->child_logs);
|
| 1232 |
|
| 1233 | bioset_exit(&ppl_conf->bs);
|
| 1234 | bioset_exit(&ppl_conf->flush_bs);
|
| 1235 | mempool_exit(&ppl_conf->io_pool);
|
| 1236 | kmem_cache_destroy(ppl_conf->io_kc);
|
| 1237 |
|
| 1238 | kfree(ppl_conf);
|
| 1239 | }
|
| 1240 |
|
| 1241 | void ppl_exit_log(struct r5conf *conf)
|
| 1242 | {
|
| 1243 | struct ppl_conf *ppl_conf = conf->log_private;
|
| 1244 |
|
| 1245 | if (ppl_conf) {
|
| 1246 | __ppl_exit_log(ppl_conf);
|
| 1247 | conf->log_private = NULL;
|
| 1248 | }
|
| 1249 | }
|
| 1250 |
|
| 1251 | static int ppl_validate_rdev(struct md_rdev *rdev)
|
| 1252 | {
|
| 1253 | int ppl_data_sectors;
|
| 1254 | int ppl_size_new;
|
| 1255 |
|
| 1256 | |
| 1257 | * The configured PPL size must be enough to store
|
| 1258 | * the header and (at the very least) partial parity
|
| 1259 | * for one stripe. Round it down to ensure the data
|
| 1260 | * space is cleanly divisible by stripe size.
|
| 1261 |
|
| 1262 | ppl_data_sectors = rdev->ppl.size - (PPL_HEADER_SIZE >> 9);
|
| 1263 |
|
| 1264 | if (ppl_data_sectors > 0)
|
| 1265 | ppl_data_sectors = rounddown(ppl_data_sectors,
|
| 1266 | RAID5_STRIPE_SECTORS((struct r5conf *)rdev->mddev->private));
|
| 1267 |
|
| 1268 | if (ppl_data_sectors <= 0) {
|
| 1269 | pr_warn("md/raid:%s: PPL space too small on %pg\n",
|
| 1270 | mdname(rdev->mddev), rdev->bdev);
|
| 1271 | return -ENOSPC;
|
| 1272 | }
|
| 1273 |
|
| 1274 | ppl_size_new = ppl_data_sectors + (PPL_HEADER_SIZE >> 9);
|
| 1275 |
|
| 1276 | if ((rdev->ppl.sector < rdev->data_offset &&
|
| 1277 | rdev->ppl.sector + ppl_size_new > rdev->data_offset) ||
|
| 1278 | (rdev->ppl.sector >= rdev->data_offset &&
|
| 1279 | rdev->data_offset + rdev->sectors > rdev->ppl.sector)) {
|
| 1280 | pr_warn("md/raid:%s: PPL space overlaps with data on %pg\n",
|
| 1281 | mdname(rdev->mddev), rdev->bdev);
|
| 1282 | return -EINVAL;
|
| 1283 | }
|
| 1284 |
|
| 1285 | if (!rdev->mddev->external &&
|
| 1286 | ((rdev->ppl.offset > 0 && rdev->ppl.offset < (rdev->sb_size >> 9)) ||
|
| 1287 | (rdev->ppl.offset <= 0 && rdev->ppl.offset + ppl_size_new > 0))) {
|
| 1288 | pr_warn("md/raid:%s: PPL space overlaps with superblock on %pg\n",
|
| 1289 | mdname(rdev->mddev), rdev->bdev);
|
| 1290 | return -EINVAL;
|
| 1291 | }
|
| 1292 |
|
| 1293 | rdev->ppl.size = ppl_size_new;
|
| 1294 |
|
| 1295 | return 0;
|
| 1296 | }
|
| 1297 |
|
| 1298 | static void ppl_init_child_log(struct ppl_log *log, struct md_rdev *rdev)
|
| 1299 | {
|
| 1300 | if ((rdev->ppl.size << 9) >= (PPL_SPACE_SIZE +
|
| 1301 | PPL_HEADER_SIZE) * 2) {
|
| 1302 | log->use_multippl = true;
|
| 1303 | set_bit(MD_HAS_MULTIPLE_PPLS,
|
| 1304 | &log->ppl_conf->mddev->flags);
|
| 1305 | log->entry_space = PPL_SPACE_SIZE;
|
| 1306 | } else {
|
| 1307 | log->use_multippl = false;
|
| 1308 | log->entry_space = (log->rdev->ppl.size << 9) -
|
| 1309 | PPL_HEADER_SIZE;
|
| 1310 | }
|
| 1311 | log->next_io_sector = rdev->ppl.sector;
|
| 1312 |
|
| 1313 | if (bdev_write_cache(rdev->bdev))
|
| 1314 | log->wb_cache_on = true;
|
| 1315 | }
|
| 1316 |
|
| 1317 | int ppl_init_log(struct r5conf *conf)
|
| 1318 | {
|
| 1319 | struct ppl_conf *ppl_conf;
|
| 1320 | struct mddev *mddev = conf->mddev;
|
| 1321 | int ret = 0;
|
| 1322 | int max_disks;
|
| 1323 | int i;
|
| 1324 |
|
| 1325 | pr_debug("md/raid:%s: enabling distributed Partial Parity Log\n",
|
| 1326 | mdname(conf->mddev));
|
| 1327 |
|
| 1328 | if (PAGE_SIZE != 4096)
|
| 1329 | return -EINVAL;
|
| 1330 |
|
| 1331 | if (mddev->level != 5) {
|
| 1332 | pr_warn("md/raid:%s PPL is not compatible with raid level %d\n",
|
| 1333 | mdname(mddev), mddev->level);
|
| 1334 | return -EINVAL;
|
| 1335 | }
|
| 1336 |
|
| 1337 | if (mddev->bitmap_info.file || mddev->bitmap_info.offset) {
|
| 1338 | pr_warn("md/raid:%s PPL is not compatible with bitmap\n",
|
| 1339 | mdname(mddev));
|
| 1340 | return -EINVAL;
|
| 1341 | }
|
| 1342 |
|
| 1343 | if (test_bit(MD_HAS_JOURNAL, &mddev->flags)) {
|
| 1344 | pr_warn("md/raid:%s PPL is not compatible with journal\n",
|
| 1345 | mdname(mddev));
|
| 1346 | return -EINVAL;
|
| 1347 | }
|
| 1348 |
|
| 1349 | max_disks = sizeof_field(struct ppl_log, disk_flush_bitmap) *
|
| 1350 | BITS_PER_BYTE;
|
| 1351 | if (conf->raid_disks > max_disks) {
|
| 1352 | pr_warn("md/raid:%s PPL doesn't support over %d disks in the array\n",
|
| 1353 | mdname(mddev), max_disks);
|
| 1354 | return -EINVAL;
|
| 1355 | }
|
| 1356 |
|
| 1357 | ppl_conf = kzalloc_obj(struct ppl_conf);
|
| 1358 | if (!ppl_conf)
|
| 1359 | return -ENOMEM;
|
| 1360 |
|
| 1361 | ppl_conf->mddev = mddev;
|
| 1362 |
|
| 1363 | ppl_conf->io_kc = KMEM_CACHE(ppl_io_unit, 0);
|
| 1364 | if (!ppl_conf->io_kc) {
|
| 1365 | ret = -ENOMEM;
|
| 1366 | goto err;
|
| 1367 | }
|
| 1368 |
|
| 1369 | ret = mempool_init(&ppl_conf->io_pool, conf->raid_disks, ppl_io_pool_alloc,
|
| 1370 | ppl_io_pool_free, ppl_conf->io_kc);
|
| 1371 | if (ret)
|
| 1372 | goto err;
|
| 1373 |
|
| 1374 | ret = bioset_init(&ppl_conf->bs, conf->raid_disks, 0, BIOSET_NEED_BVECS);
|
| 1375 | if (ret)
|
| 1376 | goto err;
|
| 1377 |
|
| 1378 | ret = bioset_init(&ppl_conf->flush_bs, conf->raid_disks, 0, 0);
|
| 1379 | if (ret)
|
| 1380 | goto err;
|
| 1381 |
|
| 1382 | ppl_conf->count = conf->raid_disks;
|
| 1383 | ppl_conf->child_logs = kzalloc_objs(struct ppl_log, ppl_conf->count);
|
| 1384 | if (!ppl_conf->child_logs) {
|
| 1385 | ret = -ENOMEM;
|
| 1386 | goto err;
|
| 1387 | }
|
| 1388 |
|
| 1389 | atomic64_set(&ppl_conf->seq, 0);
|
| 1390 | INIT_LIST_HEAD(&ppl_conf->no_mem_stripes);
|
| 1391 | spin_lock_init(&ppl_conf->no_mem_stripes_lock);
|
| 1392 |
|
| 1393 | if (!mddev->external) {
|
| 1394 | ppl_conf->signature = ~crc32c(~0, mddev->uuid, sizeof(mddev->uuid));
|
| 1395 | ppl_conf->block_size = 512;
|
| 1396 | } else {
|
| 1397 | ppl_conf->block_size =
|
| 1398 | queue_logical_block_size(mddev->gendisk->queue);
|
| 1399 | }
|
| 1400 |
|
| 1401 | for (i = 0; i < ppl_conf->count; i++) {
|
| 1402 | struct ppl_log *log = &ppl_conf->child_logs[i];
|
| 1403 | struct md_rdev *rdev = conf->disks[i].rdev;
|
| 1404 |
|
| 1405 | mutex_init(&log->io_mutex);
|
| 1406 | spin_lock_init(&log->io_list_lock);
|
| 1407 | INIT_LIST_HEAD(&log->io_list);
|
| 1408 |
|
| 1409 | log->ppl_conf = ppl_conf;
|
| 1410 | log->rdev = rdev;
|
| 1411 |
|
| 1412 | if (rdev) {
|
| 1413 | ret = ppl_validate_rdev(rdev);
|
| 1414 | if (ret)
|
| 1415 | goto err;
|
| 1416 |
|
| 1417 | ppl_init_child_log(log, rdev);
|
| 1418 | }
|
| 1419 | }
|
| 1420 |
|
| 1421 |
|
| 1422 | ret = ppl_load(ppl_conf);
|
| 1423 |
|
| 1424 | if (ret) {
|
| 1425 | goto err;
|
| 1426 | } else if (!mddev->pers && mddev->resync_offset == 0 &&
|
| 1427 | ppl_conf->recovered_entries > 0 &&
|
| 1428 | ppl_conf->mismatch_count == 0) {
|
| 1429 | |
| 1430 | * If we are starting a dirty array and the recovery succeeds
|
| 1431 | * without any issues, set the array as clean.
|
| 1432 |
|
| 1433 | mddev->resync_offset = MaxSector;
|
| 1434 | set_bit(MD_SB_CHANGE_CLEAN, &mddev->sb_flags);
|
| 1435 | } else if (mddev->pers && ppl_conf->mismatch_count > 0) {
|
| 1436 |
|
| 1437 | ret = -EINVAL;
|
| 1438 | goto err;
|
| 1439 | }
|
| 1440 |
|
| 1441 | conf->log_private = ppl_conf;
|
| 1442 | set_bit(MD_HAS_PPL, &ppl_conf->mddev->flags);
|
| 1443 |
|
| 1444 | return 0;
|
| 1445 | err:
|
| 1446 | __ppl_exit_log(ppl_conf);
|
| 1447 | return ret;
|
| 1448 | }
|
| 1449 |
|
| 1450 | int ppl_modify_log(struct r5conf *conf, struct md_rdev *rdev, bool add)
|
| 1451 | {
|
| 1452 | struct ppl_conf *ppl_conf = conf->log_private;
|
| 1453 | struct ppl_log *log;
|
| 1454 | int ret = 0;
|
| 1455 |
|
| 1456 | if (!rdev)
|
| 1457 | return -EINVAL;
|
| 1458 |
|
| 1459 | pr_debug("%s: disk: %d operation: %s dev: %pg\n",
|
| 1460 | __func__, rdev->raid_disk, add ? "add" : "remove",
|
| 1461 | rdev->bdev);
|
| 1462 |
|
| 1463 | if (rdev->raid_disk < 0)
|
| 1464 | return 0;
|
| 1465 |
|
| 1466 | if (rdev->raid_disk >= ppl_conf->count)
|
| 1467 | return -ENODEV;
|
| 1468 |
|
| 1469 | log = &ppl_conf->child_logs[rdev->raid_disk];
|
| 1470 |
|
| 1471 | mutex_lock(&log->io_mutex);
|
| 1472 | if (add) {
|
| 1473 | ret = ppl_validate_rdev(rdev);
|
| 1474 | if (!ret) {
|
| 1475 | log->rdev = rdev;
|
| 1476 | ret = ppl_write_empty_header(log);
|
| 1477 | ppl_init_child_log(log, rdev);
|
| 1478 | }
|
| 1479 | } else {
|
| 1480 | log->rdev = NULL;
|
| 1481 | }
|
| 1482 | mutex_unlock(&log->io_mutex);
|
| 1483 |
|
| 1484 | return ret;
|
| 1485 | }
|
| 1486 |
|
| 1487 | static ssize_t
|
| 1488 | ppl_write_hint_show(struct mddev *mddev, char *buf)
|
| 1489 | {
|
| 1490 | return sprintf(buf, "%d\n", 0);
|
| 1491 | }
|
| 1492 |
|
| 1493 | static ssize_t
|
| 1494 | ppl_write_hint_store(struct mddev *mddev, const char *page, size_t len)
|
| 1495 | {
|
| 1496 | struct r5conf *conf;
|
| 1497 | int err = 0;
|
| 1498 | unsigned short new;
|
| 1499 |
|
| 1500 | if (len >= PAGE_SIZE)
|
| 1501 | return -EINVAL;
|
| 1502 | if (kstrtou16(page, 10, &new))
|
| 1503 | return -EINVAL;
|
| 1504 |
|
| 1505 | err = mddev_lock(mddev);
|
| 1506 | if (err)
|
| 1507 | return err;
|
| 1508 |
|
| 1509 | conf = mddev->private;
|
| 1510 | if (!conf)
|
| 1511 | err = -ENODEV;
|
| 1512 | else if (!raid5_has_ppl(conf) || !conf->log_private)
|
| 1513 | err = -EINVAL;
|
| 1514 |
|
| 1515 | mddev_unlock(mddev);
|
| 1516 |
|
| 1517 | return err ?: len;
|
| 1518 | }
|
| 1519 |
|
| 1520 | struct md_sysfs_entry
|
| 1521 | ppl_write_hint = __ATTR(ppl_write_hint, S_IRUGO | S_IWUSR,
|
| 1522 | ppl_write_hint_show,
|
| 1523 | ppl_write_hint_store);
|