11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * raid1.c : Multiple Devices driver for Linux 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman 71da177e4SLinus Torvalds * 81da177e4SLinus Torvalds * RAID-1 management functions. 91da177e4SLinus Torvalds * 101da177e4SLinus Torvalds * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000 111da177e4SLinus Torvalds * 1296de0e25SJan Engelhardt * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk> 131da177e4SLinus Torvalds * Various fixes by Neil Brown <neilb@cse.unsw.edu.au> 141da177e4SLinus Torvalds * 15191ea9b2SNeilBrown * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support 16191ea9b2SNeilBrown * bitmapped intelligence in resync: 17191ea9b2SNeilBrown * 18191ea9b2SNeilBrown * - bitmap marked during normal i/o 19191ea9b2SNeilBrown * - bitmap used to skip nondirty blocks during sync 20191ea9b2SNeilBrown * 21191ea9b2SNeilBrown * Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology: 22191ea9b2SNeilBrown * - persistent bitmap code 23191ea9b2SNeilBrown * 241da177e4SLinus Torvalds * This program is free software; you can redistribute it and/or modify 251da177e4SLinus Torvalds * it under the terms of the GNU General Public License as published by 261da177e4SLinus Torvalds * the Free Software Foundation; either version 2, or (at your option) 271da177e4SLinus Torvalds * any later version. 281da177e4SLinus Torvalds * 291da177e4SLinus Torvalds * You should have received a copy of the GNU General Public License 301da177e4SLinus Torvalds * (for example /usr/src/linux/COPYING); if not, write to the Free 311da177e4SLinus Torvalds * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 321da177e4SLinus Torvalds */ 331da177e4SLinus Torvalds 3425570727SStephen Rothwell #include <linux/delay.h> 35bff61975SNeilBrown #include <linux/blkdev.h> 36bff61975SNeilBrown #include <linux/seq_file.h> 3743b2e5d8SNeilBrown #include "md.h" 38ef740c37SChristoph Hellwig #include "raid1.h" 39ef740c37SChristoph Hellwig #include "bitmap.h" 40191ea9b2SNeilBrown 41191ea9b2SNeilBrown #define DEBUG 0 42191ea9b2SNeilBrown #if DEBUG 43191ea9b2SNeilBrown #define PRINTK(x...) printk(x) 44191ea9b2SNeilBrown #else 45191ea9b2SNeilBrown #define PRINTK(x...) 46191ea9b2SNeilBrown #endif 471da177e4SLinus Torvalds 481da177e4SLinus Torvalds /* 491da177e4SLinus Torvalds * Number of guaranteed r1bios in case of extreme VM load: 501da177e4SLinus Torvalds */ 511da177e4SLinus Torvalds #define NR_RAID1_BIOS 256 521da177e4SLinus Torvalds 531da177e4SLinus Torvalds 541da177e4SLinus Torvalds static void unplug_slaves(mddev_t *mddev); 551da177e4SLinus Torvalds 5617999be4SNeilBrown static void allow_barrier(conf_t *conf); 5717999be4SNeilBrown static void lower_barrier(conf_t *conf); 581da177e4SLinus Torvalds 59dd0fc66fSAl Viro static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data) 601da177e4SLinus Torvalds { 611da177e4SLinus Torvalds struct pool_info *pi = data; 621da177e4SLinus Torvalds r1bio_t *r1_bio; 631da177e4SLinus Torvalds int size = offsetof(r1bio_t, bios[pi->raid_disks]); 641da177e4SLinus Torvalds 651da177e4SLinus Torvalds /* allocate a r1bio with room for raid_disks entries in the bios array */ 669ffae0cfSNeilBrown r1_bio = kzalloc(size, gfp_flags); 67ed9bfdf1SNeilBrown if (!r1_bio && pi->mddev) 681da177e4SLinus Torvalds unplug_slaves(pi->mddev); 691da177e4SLinus Torvalds 701da177e4SLinus Torvalds return r1_bio; 711da177e4SLinus Torvalds } 721da177e4SLinus Torvalds 731da177e4SLinus Torvalds static void r1bio_pool_free(void *r1_bio, void *data) 741da177e4SLinus Torvalds { 751da177e4SLinus Torvalds kfree(r1_bio); 761da177e4SLinus Torvalds } 771da177e4SLinus Torvalds 781da177e4SLinus Torvalds #define RESYNC_BLOCK_SIZE (64*1024) 791da177e4SLinus Torvalds //#define RESYNC_BLOCK_SIZE PAGE_SIZE 801da177e4SLinus Torvalds #define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9) 811da177e4SLinus Torvalds #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE) 821da177e4SLinus Torvalds #define RESYNC_WINDOW (2048*1024) 831da177e4SLinus Torvalds 84dd0fc66fSAl Viro static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data) 851da177e4SLinus Torvalds { 861da177e4SLinus Torvalds struct pool_info *pi = data; 871da177e4SLinus Torvalds struct page *page; 881da177e4SLinus Torvalds r1bio_t *r1_bio; 891da177e4SLinus Torvalds struct bio *bio; 901da177e4SLinus Torvalds int i, j; 911da177e4SLinus Torvalds 921da177e4SLinus Torvalds r1_bio = r1bio_pool_alloc(gfp_flags, pi); 931da177e4SLinus Torvalds if (!r1_bio) { 941da177e4SLinus Torvalds unplug_slaves(pi->mddev); 951da177e4SLinus Torvalds return NULL; 961da177e4SLinus Torvalds } 971da177e4SLinus Torvalds 981da177e4SLinus Torvalds /* 991da177e4SLinus Torvalds * Allocate bios : 1 for reading, n-1 for writing 1001da177e4SLinus Torvalds */ 1011da177e4SLinus Torvalds for (j = pi->raid_disks ; j-- ; ) { 1021da177e4SLinus Torvalds bio = bio_alloc(gfp_flags, RESYNC_PAGES); 1031da177e4SLinus Torvalds if (!bio) 1041da177e4SLinus Torvalds goto out_free_bio; 1051da177e4SLinus Torvalds r1_bio->bios[j] = bio; 1061da177e4SLinus Torvalds } 1071da177e4SLinus Torvalds /* 1081da177e4SLinus Torvalds * Allocate RESYNC_PAGES data pages and attach them to 109d11c171eSNeilBrown * the first bio. 110d11c171eSNeilBrown * If this is a user-requested check/repair, allocate 111d11c171eSNeilBrown * RESYNC_PAGES for each bio. 1121da177e4SLinus Torvalds */ 113d11c171eSNeilBrown if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) 114d11c171eSNeilBrown j = pi->raid_disks; 115d11c171eSNeilBrown else 116d11c171eSNeilBrown j = 1; 117d11c171eSNeilBrown while(j--) { 118d11c171eSNeilBrown bio = r1_bio->bios[j]; 1191da177e4SLinus Torvalds for (i = 0; i < RESYNC_PAGES; i++) { 1201da177e4SLinus Torvalds page = alloc_page(gfp_flags); 1211da177e4SLinus Torvalds if (unlikely(!page)) 1221da177e4SLinus Torvalds goto out_free_pages; 1231da177e4SLinus Torvalds 1241da177e4SLinus Torvalds bio->bi_io_vec[i].bv_page = page; 125303a0e11SNeilBrown bio->bi_vcnt = i+1; 1261da177e4SLinus Torvalds } 127d11c171eSNeilBrown } 128d11c171eSNeilBrown /* If not user-requests, copy the page pointers to all bios */ 129d11c171eSNeilBrown if (!test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) { 130d11c171eSNeilBrown for (i=0; i<RESYNC_PAGES ; i++) 131d11c171eSNeilBrown for (j=1; j<pi->raid_disks; j++) 132d11c171eSNeilBrown r1_bio->bios[j]->bi_io_vec[i].bv_page = 133d11c171eSNeilBrown r1_bio->bios[0]->bi_io_vec[i].bv_page; 134d11c171eSNeilBrown } 1351da177e4SLinus Torvalds 1361da177e4SLinus Torvalds r1_bio->master_bio = NULL; 1371da177e4SLinus Torvalds 1381da177e4SLinus Torvalds return r1_bio; 1391da177e4SLinus Torvalds 1401da177e4SLinus Torvalds out_free_pages: 141d11c171eSNeilBrown for (j=0 ; j < pi->raid_disks; j++) 142303a0e11SNeilBrown for (i=0; i < r1_bio->bios[j]->bi_vcnt ; i++) 143303a0e11SNeilBrown put_page(r1_bio->bios[j]->bi_io_vec[i].bv_page); 144d11c171eSNeilBrown j = -1; 1451da177e4SLinus Torvalds out_free_bio: 1461da177e4SLinus Torvalds while ( ++j < pi->raid_disks ) 1471da177e4SLinus Torvalds bio_put(r1_bio->bios[j]); 1481da177e4SLinus Torvalds r1bio_pool_free(r1_bio, data); 1491da177e4SLinus Torvalds return NULL; 1501da177e4SLinus Torvalds } 1511da177e4SLinus Torvalds 1521da177e4SLinus Torvalds static void r1buf_pool_free(void *__r1_bio, void *data) 1531da177e4SLinus Torvalds { 1541da177e4SLinus Torvalds struct pool_info *pi = data; 155d11c171eSNeilBrown int i,j; 1561da177e4SLinus Torvalds r1bio_t *r1bio = __r1_bio; 1571da177e4SLinus Torvalds 158d11c171eSNeilBrown for (i = 0; i < RESYNC_PAGES; i++) 159d11c171eSNeilBrown for (j = pi->raid_disks; j-- ;) { 160d11c171eSNeilBrown if (j == 0 || 161d11c171eSNeilBrown r1bio->bios[j]->bi_io_vec[i].bv_page != 162d11c171eSNeilBrown r1bio->bios[0]->bi_io_vec[i].bv_page) 1631345b1d8SNeilBrown safe_put_page(r1bio->bios[j]->bi_io_vec[i].bv_page); 1641da177e4SLinus Torvalds } 1651da177e4SLinus Torvalds for (i=0 ; i < pi->raid_disks; i++) 1661da177e4SLinus Torvalds bio_put(r1bio->bios[i]); 1671da177e4SLinus Torvalds 1681da177e4SLinus Torvalds r1bio_pool_free(r1bio, data); 1691da177e4SLinus Torvalds } 1701da177e4SLinus Torvalds 1711da177e4SLinus Torvalds static void put_all_bios(conf_t *conf, r1bio_t *r1_bio) 1721da177e4SLinus Torvalds { 1731da177e4SLinus Torvalds int i; 1741da177e4SLinus Torvalds 1751da177e4SLinus Torvalds for (i = 0; i < conf->raid_disks; i++) { 1761da177e4SLinus Torvalds struct bio **bio = r1_bio->bios + i; 177cf30a473SNeilBrown if (*bio && *bio != IO_BLOCKED) 1781da177e4SLinus Torvalds bio_put(*bio); 1791da177e4SLinus Torvalds *bio = NULL; 1801da177e4SLinus Torvalds } 1811da177e4SLinus Torvalds } 1821da177e4SLinus Torvalds 183858119e1SArjan van de Ven static void free_r1bio(r1bio_t *r1_bio) 1841da177e4SLinus Torvalds { 185070ec55dSNeilBrown conf_t *conf = r1_bio->mddev->private; 1861da177e4SLinus Torvalds 1871da177e4SLinus Torvalds /* 1881da177e4SLinus Torvalds * Wake up any possible resync thread that waits for the device 1891da177e4SLinus Torvalds * to go idle. 1901da177e4SLinus Torvalds */ 19117999be4SNeilBrown allow_barrier(conf); 1921da177e4SLinus Torvalds 1931da177e4SLinus Torvalds put_all_bios(conf, r1_bio); 1941da177e4SLinus Torvalds mempool_free(r1_bio, conf->r1bio_pool); 1951da177e4SLinus Torvalds } 1961da177e4SLinus Torvalds 197858119e1SArjan van de Ven static void put_buf(r1bio_t *r1_bio) 1981da177e4SLinus Torvalds { 199070ec55dSNeilBrown conf_t *conf = r1_bio->mddev->private; 2003e198f78SNeilBrown int i; 2013e198f78SNeilBrown 2023e198f78SNeilBrown for (i=0; i<conf->raid_disks; i++) { 2033e198f78SNeilBrown struct bio *bio = r1_bio->bios[i]; 2043e198f78SNeilBrown if (bio->bi_end_io) 2053e198f78SNeilBrown rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev); 2063e198f78SNeilBrown } 2071da177e4SLinus Torvalds 2081da177e4SLinus Torvalds mempool_free(r1_bio, conf->r1buf_pool); 2091da177e4SLinus Torvalds 21017999be4SNeilBrown lower_barrier(conf); 2111da177e4SLinus Torvalds } 2121da177e4SLinus Torvalds 2131da177e4SLinus Torvalds static void reschedule_retry(r1bio_t *r1_bio) 2141da177e4SLinus Torvalds { 2151da177e4SLinus Torvalds unsigned long flags; 2161da177e4SLinus Torvalds mddev_t *mddev = r1_bio->mddev; 217070ec55dSNeilBrown conf_t *conf = mddev->private; 2181da177e4SLinus Torvalds 2191da177e4SLinus Torvalds spin_lock_irqsave(&conf->device_lock, flags); 2201da177e4SLinus Torvalds list_add(&r1_bio->retry_list, &conf->retry_list); 221ddaf22abSNeilBrown conf->nr_queued ++; 2221da177e4SLinus Torvalds spin_unlock_irqrestore(&conf->device_lock, flags); 2231da177e4SLinus Torvalds 22417999be4SNeilBrown wake_up(&conf->wait_barrier); 2251da177e4SLinus Torvalds md_wakeup_thread(mddev->thread); 2261da177e4SLinus Torvalds } 2271da177e4SLinus Torvalds 2281da177e4SLinus Torvalds /* 2291da177e4SLinus Torvalds * raid_end_bio_io() is called when we have finished servicing a mirrored 2301da177e4SLinus Torvalds * operation and are ready to return a success/failure code to the buffer 2311da177e4SLinus Torvalds * cache layer. 2321da177e4SLinus Torvalds */ 2331da177e4SLinus Torvalds static void raid_end_bio_io(r1bio_t *r1_bio) 2341da177e4SLinus Torvalds { 2351da177e4SLinus Torvalds struct bio *bio = r1_bio->master_bio; 2361da177e4SLinus Torvalds 2374b6d287fSNeilBrown /* if nobody has done the final endio yet, do it now */ 2384b6d287fSNeilBrown if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) { 2394b6d287fSNeilBrown PRINTK(KERN_DEBUG "raid1: sync end %s on sectors %llu-%llu\n", 2404b6d287fSNeilBrown (bio_data_dir(bio) == WRITE) ? "write" : "read", 2414b6d287fSNeilBrown (unsigned long long) bio->bi_sector, 2424b6d287fSNeilBrown (unsigned long long) bio->bi_sector + 2434b6d287fSNeilBrown (bio->bi_size >> 9) - 1); 2444b6d287fSNeilBrown 2456712ecf8SNeilBrown bio_endio(bio, 2461da177e4SLinus Torvalds test_bit(R1BIO_Uptodate, &r1_bio->state) ? 0 : -EIO); 2474b6d287fSNeilBrown } 2481da177e4SLinus Torvalds free_r1bio(r1_bio); 2491da177e4SLinus Torvalds } 2501da177e4SLinus Torvalds 2511da177e4SLinus Torvalds /* 2521da177e4SLinus Torvalds * Update disk head position estimator based on IRQ completion info. 2531da177e4SLinus Torvalds */ 2541da177e4SLinus Torvalds static inline void update_head_pos(int disk, r1bio_t *r1_bio) 2551da177e4SLinus Torvalds { 256070ec55dSNeilBrown conf_t *conf = r1_bio->mddev->private; 2571da177e4SLinus Torvalds 2581da177e4SLinus Torvalds conf->mirrors[disk].head_position = 2591da177e4SLinus Torvalds r1_bio->sector + (r1_bio->sectors); 2601da177e4SLinus Torvalds } 2611da177e4SLinus Torvalds 2626712ecf8SNeilBrown static void raid1_end_read_request(struct bio *bio, int error) 2631da177e4SLinus Torvalds { 2641da177e4SLinus Torvalds int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); 2657b92813cSH Hartley Sweeten r1bio_t *r1_bio = bio->bi_private; 2661da177e4SLinus Torvalds int mirror; 267070ec55dSNeilBrown conf_t *conf = r1_bio->mddev->private; 2681da177e4SLinus Torvalds 2691da177e4SLinus Torvalds mirror = r1_bio->read_disk; 2701da177e4SLinus Torvalds /* 2711da177e4SLinus Torvalds * this branch is our 'one mirror IO has finished' event handler: 2721da177e4SLinus Torvalds */ 273ddaf22abSNeilBrown update_head_pos(mirror, r1_bio); 274ddaf22abSNeilBrown 275220946c9SNeilBrown if (uptodate) 2761da177e4SLinus Torvalds set_bit(R1BIO_Uptodate, &r1_bio->state); 277dd00a99eSNeilBrown else { 278dd00a99eSNeilBrown /* If all other devices have failed, we want to return 279dd00a99eSNeilBrown * the error upwards rather than fail the last device. 280dd00a99eSNeilBrown * Here we redefine "uptodate" to mean "Don't want to retry" 281dd00a99eSNeilBrown */ 282dd00a99eSNeilBrown unsigned long flags; 283dd00a99eSNeilBrown spin_lock_irqsave(&conf->device_lock, flags); 284dd00a99eSNeilBrown if (r1_bio->mddev->degraded == conf->raid_disks || 285dd00a99eSNeilBrown (r1_bio->mddev->degraded == conf->raid_disks-1 && 286dd00a99eSNeilBrown !test_bit(Faulty, &conf->mirrors[mirror].rdev->flags))) 287dd00a99eSNeilBrown uptodate = 1; 288dd00a99eSNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 289dd00a99eSNeilBrown } 2901da177e4SLinus Torvalds 291dd00a99eSNeilBrown if (uptodate) 2921da177e4SLinus Torvalds raid_end_bio_io(r1_bio); 293dd00a99eSNeilBrown else { 2941da177e4SLinus Torvalds /* 2951da177e4SLinus Torvalds * oops, read error: 2961da177e4SLinus Torvalds */ 2971da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 2981da177e4SLinus Torvalds if (printk_ratelimit()) 2999dd1e2faSNeilBrown printk(KERN_ERR "md/raid1:%s: %s: rescheduling sector %llu\n", 3009dd1e2faSNeilBrown mdname(conf->mddev), 3011da177e4SLinus Torvalds bdevname(conf->mirrors[mirror].rdev->bdev,b), (unsigned long long)r1_bio->sector); 3021da177e4SLinus Torvalds reschedule_retry(r1_bio); 3031da177e4SLinus Torvalds } 3041da177e4SLinus Torvalds 3051da177e4SLinus Torvalds rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); 3061da177e4SLinus Torvalds } 3071da177e4SLinus Torvalds 3086712ecf8SNeilBrown static void raid1_end_write_request(struct bio *bio, int error) 3091da177e4SLinus Torvalds { 3101da177e4SLinus Torvalds int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); 3117b92813cSH Hartley Sweeten r1bio_t *r1_bio = bio->bi_private; 312a9701a30SNeilBrown int mirror, behind = test_bit(R1BIO_BehindIO, &r1_bio->state); 313070ec55dSNeilBrown conf_t *conf = r1_bio->mddev->private; 31404b857f7SNeilBrown struct bio *to_put = NULL; 3151da177e4SLinus Torvalds 3161da177e4SLinus Torvalds 3171da177e4SLinus Torvalds for (mirror = 0; mirror < conf->raid_disks; mirror++) 3181da177e4SLinus Torvalds if (r1_bio->bios[mirror] == bio) 3191da177e4SLinus Torvalds break; 3201da177e4SLinus Torvalds 321bea27718SNeilBrown if (error == -EOPNOTSUPP && test_bit(R1BIO_Barrier, &r1_bio->state)) { 322a9701a30SNeilBrown set_bit(BarriersNotsupp, &conf->mirrors[mirror].rdev->flags); 323a9701a30SNeilBrown set_bit(R1BIO_BarrierRetry, &r1_bio->state); 324a9701a30SNeilBrown r1_bio->mddev->barriers_work = 0; 3255e7dd2abSNeilBrown /* Don't rdev_dec_pending in this branch - keep it for the retry */ 326a9701a30SNeilBrown } else { 3271da177e4SLinus Torvalds /* 3281da177e4SLinus Torvalds * this branch is our 'one mirror IO has finished' event handler: 3291da177e4SLinus Torvalds */ 330a9701a30SNeilBrown r1_bio->bios[mirror] = NULL; 33104b857f7SNeilBrown to_put = bio; 332191ea9b2SNeilBrown if (!uptodate) { 3331da177e4SLinus Torvalds md_error(r1_bio->mddev, conf->mirrors[mirror].rdev); 334191ea9b2SNeilBrown /* an I/O failed, we can't clear the bitmap */ 335191ea9b2SNeilBrown set_bit(R1BIO_Degraded, &r1_bio->state); 336191ea9b2SNeilBrown } else 3371da177e4SLinus Torvalds /* 3381da177e4SLinus Torvalds * Set R1BIO_Uptodate in our master bio, so that 3391da177e4SLinus Torvalds * we will return a good error code for to the higher 3401da177e4SLinus Torvalds * levels even if IO on some other mirrored buffer fails. 3411da177e4SLinus Torvalds * 3421da177e4SLinus Torvalds * The 'master' represents the composite IO operation to 3431da177e4SLinus Torvalds * user-side. So if something waits for IO, then it will 3441da177e4SLinus Torvalds * wait for the 'master' bio. 3451da177e4SLinus Torvalds */ 3461da177e4SLinus Torvalds set_bit(R1BIO_Uptodate, &r1_bio->state); 3471da177e4SLinus Torvalds 3481da177e4SLinus Torvalds update_head_pos(mirror, r1_bio); 3491da177e4SLinus Torvalds 3504b6d287fSNeilBrown if (behind) { 3514b6d287fSNeilBrown if (test_bit(WriteMostly, &conf->mirrors[mirror].rdev->flags)) 3524b6d287fSNeilBrown atomic_dec(&r1_bio->behind_remaining); 3534b6d287fSNeilBrown 3544b6d287fSNeilBrown /* In behind mode, we ACK the master bio once the I/O has safely 3554b6d287fSNeilBrown * reached all non-writemostly disks. Setting the Returned bit 3564b6d287fSNeilBrown * ensures that this gets done only once -- we don't ever want to 3574b6d287fSNeilBrown * return -EIO here, instead we'll wait */ 3584b6d287fSNeilBrown 3594b6d287fSNeilBrown if (atomic_read(&r1_bio->behind_remaining) >= (atomic_read(&r1_bio->remaining)-1) && 3604b6d287fSNeilBrown test_bit(R1BIO_Uptodate, &r1_bio->state)) { 3614b6d287fSNeilBrown /* Maybe we can return now */ 3624b6d287fSNeilBrown if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) { 3634b6d287fSNeilBrown struct bio *mbio = r1_bio->master_bio; 3644b6d287fSNeilBrown PRINTK(KERN_DEBUG "raid1: behind end write sectors %llu-%llu\n", 3654b6d287fSNeilBrown (unsigned long long) mbio->bi_sector, 3664b6d287fSNeilBrown (unsigned long long) mbio->bi_sector + 3674b6d287fSNeilBrown (mbio->bi_size >> 9) - 1); 3686712ecf8SNeilBrown bio_endio(mbio, 0); 3694b6d287fSNeilBrown } 3704b6d287fSNeilBrown } 3714b6d287fSNeilBrown } 3725e7dd2abSNeilBrown rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); 373a9701a30SNeilBrown } 3741da177e4SLinus Torvalds /* 3751da177e4SLinus Torvalds * 3761da177e4SLinus Torvalds * Let's see if all mirrored write operations have finished 3771da177e4SLinus Torvalds * already. 3781da177e4SLinus Torvalds */ 3791da177e4SLinus Torvalds if (atomic_dec_and_test(&r1_bio->remaining)) { 380c70810b3SNeilBrown if (test_bit(R1BIO_BarrierRetry, &r1_bio->state)) 381a9701a30SNeilBrown reschedule_retry(r1_bio); 382c70810b3SNeilBrown else { 3835e7dd2abSNeilBrown /* it really is the end of this request */ 3844b6d287fSNeilBrown if (test_bit(R1BIO_BehindIO, &r1_bio->state)) { 3854b6d287fSNeilBrown /* free extra copy of the data pages */ 3864b6d287fSNeilBrown int i = bio->bi_vcnt; 3874b6d287fSNeilBrown while (i--) 3881345b1d8SNeilBrown safe_put_page(bio->bi_io_vec[i].bv_page); 3894b6d287fSNeilBrown } 390191ea9b2SNeilBrown /* clear the bitmap if all writes complete successfully */ 391191ea9b2SNeilBrown bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector, 392191ea9b2SNeilBrown r1_bio->sectors, 3934b6d287fSNeilBrown !test_bit(R1BIO_Degraded, &r1_bio->state), 3944b6d287fSNeilBrown behind); 3951da177e4SLinus Torvalds md_write_end(r1_bio->mddev); 3961da177e4SLinus Torvalds raid_end_bio_io(r1_bio); 3971da177e4SLinus Torvalds } 398c70810b3SNeilBrown } 399c70810b3SNeilBrown 40004b857f7SNeilBrown if (to_put) 40104b857f7SNeilBrown bio_put(to_put); 4021da177e4SLinus Torvalds } 4031da177e4SLinus Torvalds 4041da177e4SLinus Torvalds 4051da177e4SLinus Torvalds /* 4061da177e4SLinus Torvalds * This routine returns the disk from which the requested read should 4071da177e4SLinus Torvalds * be done. There is a per-array 'next expected sequential IO' sector 4081da177e4SLinus Torvalds * number - if this matches on the next IO then we use the last disk. 4091da177e4SLinus Torvalds * There is also a per-disk 'last know head position' sector that is 4101da177e4SLinus Torvalds * maintained from IRQ contexts, both the normal and the resync IO 4111da177e4SLinus Torvalds * completion handlers update this position correctly. If there is no 4121da177e4SLinus Torvalds * perfect sequential match then we pick the disk whose head is closest. 4131da177e4SLinus Torvalds * 4141da177e4SLinus Torvalds * If there are 2 mirrors in the same 2 devices, performance degrades 4151da177e4SLinus Torvalds * because position is mirror, not device based. 4161da177e4SLinus Torvalds * 4171da177e4SLinus Torvalds * The rdev for the device selected will have nr_pending incremented. 4181da177e4SLinus Torvalds */ 4191da177e4SLinus Torvalds static int read_balance(conf_t *conf, r1bio_t *r1_bio) 4201da177e4SLinus Torvalds { 4211da177e4SLinus Torvalds const unsigned long this_sector = r1_bio->sector; 4221da177e4SLinus Torvalds int new_disk = conf->last_used, disk = new_disk; 4238ddf9efeSNeilBrown int wonly_disk = -1; 4241da177e4SLinus Torvalds const int sectors = r1_bio->sectors; 4251da177e4SLinus Torvalds sector_t new_distance, current_distance; 4268ddf9efeSNeilBrown mdk_rdev_t *rdev; 4271da177e4SLinus Torvalds 4281da177e4SLinus Torvalds rcu_read_lock(); 4291da177e4SLinus Torvalds /* 4308ddf9efeSNeilBrown * Check if we can balance. We can balance on the whole 4311da177e4SLinus Torvalds * device if no resync is going on, or below the resync window. 4321da177e4SLinus Torvalds * We take the first readable disk when above the resync window. 4331da177e4SLinus Torvalds */ 4341da177e4SLinus Torvalds retry: 4351da177e4SLinus Torvalds if (conf->mddev->recovery_cp < MaxSector && 4361da177e4SLinus Torvalds (this_sector + sectors >= conf->next_resync)) { 4371da177e4SLinus Torvalds /* Choose the first operation device, for consistancy */ 4381da177e4SLinus Torvalds new_disk = 0; 4391da177e4SLinus Torvalds 440d6065f7bSSuzanne Wood for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev); 441cf30a473SNeilBrown r1_bio->bios[new_disk] == IO_BLOCKED || 442b2d444d7SNeilBrown !rdev || !test_bit(In_sync, &rdev->flags) 4438ddf9efeSNeilBrown || test_bit(WriteMostly, &rdev->flags); 444d6065f7bSSuzanne Wood rdev = rcu_dereference(conf->mirrors[++new_disk].rdev)) { 4458ddf9efeSNeilBrown 446cf30a473SNeilBrown if (rdev && test_bit(In_sync, &rdev->flags) && 447cf30a473SNeilBrown r1_bio->bios[new_disk] != IO_BLOCKED) 4488ddf9efeSNeilBrown wonly_disk = new_disk; 4498ddf9efeSNeilBrown 4508ddf9efeSNeilBrown if (new_disk == conf->raid_disks - 1) { 4518ddf9efeSNeilBrown new_disk = wonly_disk; 4521da177e4SLinus Torvalds break; 4531da177e4SLinus Torvalds } 4541da177e4SLinus Torvalds } 4551da177e4SLinus Torvalds goto rb_out; 4561da177e4SLinus Torvalds } 4571da177e4SLinus Torvalds 4581da177e4SLinus Torvalds 4591da177e4SLinus Torvalds /* make sure the disk is operational */ 460d6065f7bSSuzanne Wood for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev); 461cf30a473SNeilBrown r1_bio->bios[new_disk] == IO_BLOCKED || 462b2d444d7SNeilBrown !rdev || !test_bit(In_sync, &rdev->flags) || 4638ddf9efeSNeilBrown test_bit(WriteMostly, &rdev->flags); 464d6065f7bSSuzanne Wood rdev = rcu_dereference(conf->mirrors[new_disk].rdev)) { 4658ddf9efeSNeilBrown 466cf30a473SNeilBrown if (rdev && test_bit(In_sync, &rdev->flags) && 467cf30a473SNeilBrown r1_bio->bios[new_disk] != IO_BLOCKED) 4688ddf9efeSNeilBrown wonly_disk = new_disk; 4698ddf9efeSNeilBrown 4701da177e4SLinus Torvalds if (new_disk <= 0) 4711da177e4SLinus Torvalds new_disk = conf->raid_disks; 4721da177e4SLinus Torvalds new_disk--; 4731da177e4SLinus Torvalds if (new_disk == disk) { 4748ddf9efeSNeilBrown new_disk = wonly_disk; 4758ddf9efeSNeilBrown break; 4768ddf9efeSNeilBrown } 4778ddf9efeSNeilBrown } 4788ddf9efeSNeilBrown 4798ddf9efeSNeilBrown if (new_disk < 0) 4801da177e4SLinus Torvalds goto rb_out; 4818ddf9efeSNeilBrown 4821da177e4SLinus Torvalds disk = new_disk; 4831da177e4SLinus Torvalds /* now disk == new_disk == starting point for search */ 4841da177e4SLinus Torvalds 4851da177e4SLinus Torvalds /* 4861da177e4SLinus Torvalds * Don't change to another disk for sequential reads: 4871da177e4SLinus Torvalds */ 4881da177e4SLinus Torvalds if (conf->next_seq_sect == this_sector) 4891da177e4SLinus Torvalds goto rb_out; 4901da177e4SLinus Torvalds if (this_sector == conf->mirrors[new_disk].head_position) 4911da177e4SLinus Torvalds goto rb_out; 4921da177e4SLinus Torvalds 4931da177e4SLinus Torvalds current_distance = abs(this_sector - conf->mirrors[disk].head_position); 4941da177e4SLinus Torvalds 4951da177e4SLinus Torvalds /* Find the disk whose head is closest */ 4961da177e4SLinus Torvalds 4971da177e4SLinus Torvalds do { 4981da177e4SLinus Torvalds if (disk <= 0) 4991da177e4SLinus Torvalds disk = conf->raid_disks; 5001da177e4SLinus Torvalds disk--; 5011da177e4SLinus Torvalds 502d6065f7bSSuzanne Wood rdev = rcu_dereference(conf->mirrors[disk].rdev); 5038ddf9efeSNeilBrown 504cf30a473SNeilBrown if (!rdev || r1_bio->bios[disk] == IO_BLOCKED || 505b2d444d7SNeilBrown !test_bit(In_sync, &rdev->flags) || 5068ddf9efeSNeilBrown test_bit(WriteMostly, &rdev->flags)) 5071da177e4SLinus Torvalds continue; 5081da177e4SLinus Torvalds 5091da177e4SLinus Torvalds if (!atomic_read(&rdev->nr_pending)) { 5101da177e4SLinus Torvalds new_disk = disk; 5111da177e4SLinus Torvalds break; 5121da177e4SLinus Torvalds } 5131da177e4SLinus Torvalds new_distance = abs(this_sector - conf->mirrors[disk].head_position); 5141da177e4SLinus Torvalds if (new_distance < current_distance) { 5151da177e4SLinus Torvalds current_distance = new_distance; 5161da177e4SLinus Torvalds new_disk = disk; 5171da177e4SLinus Torvalds } 5181da177e4SLinus Torvalds } while (disk != conf->last_used); 5191da177e4SLinus Torvalds 5201da177e4SLinus Torvalds rb_out: 5211da177e4SLinus Torvalds 5221da177e4SLinus Torvalds 5231da177e4SLinus Torvalds if (new_disk >= 0) { 524d6065f7bSSuzanne Wood rdev = rcu_dereference(conf->mirrors[new_disk].rdev); 5258ddf9efeSNeilBrown if (!rdev) 5268ddf9efeSNeilBrown goto retry; 5278ddf9efeSNeilBrown atomic_inc(&rdev->nr_pending); 528b2d444d7SNeilBrown if (!test_bit(In_sync, &rdev->flags)) { 5291da177e4SLinus Torvalds /* cannot risk returning a device that failed 5301da177e4SLinus Torvalds * before we inc'ed nr_pending 5311da177e4SLinus Torvalds */ 53203c902e1SNeilBrown rdev_dec_pending(rdev, conf->mddev); 5331da177e4SLinus Torvalds goto retry; 5341da177e4SLinus Torvalds } 5358ddf9efeSNeilBrown conf->next_seq_sect = this_sector + sectors; 5368ddf9efeSNeilBrown conf->last_used = new_disk; 5371da177e4SLinus Torvalds } 5381da177e4SLinus Torvalds rcu_read_unlock(); 5391da177e4SLinus Torvalds 5401da177e4SLinus Torvalds return new_disk; 5411da177e4SLinus Torvalds } 5421da177e4SLinus Torvalds 5431da177e4SLinus Torvalds static void unplug_slaves(mddev_t *mddev) 5441da177e4SLinus Torvalds { 545070ec55dSNeilBrown conf_t *conf = mddev->private; 5461da177e4SLinus Torvalds int i; 5471da177e4SLinus Torvalds 5481da177e4SLinus Torvalds rcu_read_lock(); 5491da177e4SLinus Torvalds for (i=0; i<mddev->raid_disks; i++) { 550d6065f7bSSuzanne Wood mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); 551b2d444d7SNeilBrown if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) { 552165125e1SJens Axboe struct request_queue *r_queue = bdev_get_queue(rdev->bdev); 5531da177e4SLinus Torvalds 5541da177e4SLinus Torvalds atomic_inc(&rdev->nr_pending); 5551da177e4SLinus Torvalds rcu_read_unlock(); 5561da177e4SLinus Torvalds 5572ad8b1efSAlan D. Brunelle blk_unplug(r_queue); 5581da177e4SLinus Torvalds 5591da177e4SLinus Torvalds rdev_dec_pending(rdev, mddev); 5601da177e4SLinus Torvalds rcu_read_lock(); 5611da177e4SLinus Torvalds } 5621da177e4SLinus Torvalds } 5631da177e4SLinus Torvalds rcu_read_unlock(); 5641da177e4SLinus Torvalds } 5651da177e4SLinus Torvalds 566165125e1SJens Axboe static void raid1_unplug(struct request_queue *q) 5671da177e4SLinus Torvalds { 568191ea9b2SNeilBrown mddev_t *mddev = q->queuedata; 569191ea9b2SNeilBrown 570191ea9b2SNeilBrown unplug_slaves(mddev); 571191ea9b2SNeilBrown md_wakeup_thread(mddev->thread); 5721da177e4SLinus Torvalds } 5731da177e4SLinus Torvalds 5740d129228SNeilBrown static int raid1_congested(void *data, int bits) 5750d129228SNeilBrown { 5760d129228SNeilBrown mddev_t *mddev = data; 577070ec55dSNeilBrown conf_t *conf = mddev->private; 5780d129228SNeilBrown int i, ret = 0; 5790d129228SNeilBrown 5803fa841d7SNeilBrown if (mddev_congested(mddev, bits)) 5813fa841d7SNeilBrown return 1; 5823fa841d7SNeilBrown 5830d129228SNeilBrown rcu_read_lock(); 5840d129228SNeilBrown for (i = 0; i < mddev->raid_disks; i++) { 5850d129228SNeilBrown mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); 5860d129228SNeilBrown if (rdev && !test_bit(Faulty, &rdev->flags)) { 587165125e1SJens Axboe struct request_queue *q = bdev_get_queue(rdev->bdev); 5880d129228SNeilBrown 5890d129228SNeilBrown /* Note the '|| 1' - when read_balance prefers 5900d129228SNeilBrown * non-congested targets, it can be removed 5910d129228SNeilBrown */ 59291a9e99dSAlexander Beregalov if ((bits & (1<<BDI_async_congested)) || 1) 5930d129228SNeilBrown ret |= bdi_congested(&q->backing_dev_info, bits); 5940d129228SNeilBrown else 5950d129228SNeilBrown ret &= bdi_congested(&q->backing_dev_info, bits); 5960d129228SNeilBrown } 5970d129228SNeilBrown } 5980d129228SNeilBrown rcu_read_unlock(); 5990d129228SNeilBrown return ret; 6000d129228SNeilBrown } 6010d129228SNeilBrown 6020d129228SNeilBrown 603a35e63efSNeilBrown static int flush_pending_writes(conf_t *conf) 604a35e63efSNeilBrown { 605a35e63efSNeilBrown /* Any writes that have been queued but are awaiting 606a35e63efSNeilBrown * bitmap updates get flushed here. 607a35e63efSNeilBrown * We return 1 if any requests were actually submitted. 608a35e63efSNeilBrown */ 609a35e63efSNeilBrown int rv = 0; 610a35e63efSNeilBrown 611a35e63efSNeilBrown spin_lock_irq(&conf->device_lock); 612a35e63efSNeilBrown 613a35e63efSNeilBrown if (conf->pending_bio_list.head) { 614a35e63efSNeilBrown struct bio *bio; 615a35e63efSNeilBrown bio = bio_list_get(&conf->pending_bio_list); 616a35e63efSNeilBrown blk_remove_plug(conf->mddev->queue); 617a35e63efSNeilBrown spin_unlock_irq(&conf->device_lock); 618a35e63efSNeilBrown /* flush any pending bitmap writes to 619a35e63efSNeilBrown * disk before proceeding w/ I/O */ 620a35e63efSNeilBrown bitmap_unplug(conf->mddev->bitmap); 621a35e63efSNeilBrown 622a35e63efSNeilBrown while (bio) { /* submit pending writes */ 623a35e63efSNeilBrown struct bio *next = bio->bi_next; 624a35e63efSNeilBrown bio->bi_next = NULL; 625a35e63efSNeilBrown generic_make_request(bio); 626a35e63efSNeilBrown bio = next; 627a35e63efSNeilBrown } 628a35e63efSNeilBrown rv = 1; 629a35e63efSNeilBrown } else 630a35e63efSNeilBrown spin_unlock_irq(&conf->device_lock); 631a35e63efSNeilBrown return rv; 632a35e63efSNeilBrown } 633a35e63efSNeilBrown 63417999be4SNeilBrown /* Barriers.... 63517999be4SNeilBrown * Sometimes we need to suspend IO while we do something else, 63617999be4SNeilBrown * either some resync/recovery, or reconfigure the array. 63717999be4SNeilBrown * To do this we raise a 'barrier'. 63817999be4SNeilBrown * The 'barrier' is a counter that can be raised multiple times 63917999be4SNeilBrown * to count how many activities are happening which preclude 64017999be4SNeilBrown * normal IO. 64117999be4SNeilBrown * We can only raise the barrier if there is no pending IO. 64217999be4SNeilBrown * i.e. if nr_pending == 0. 64317999be4SNeilBrown * We choose only to raise the barrier if no-one is waiting for the 64417999be4SNeilBrown * barrier to go down. This means that as soon as an IO request 64517999be4SNeilBrown * is ready, no other operations which require a barrier will start 64617999be4SNeilBrown * until the IO request has had a chance. 64717999be4SNeilBrown * 64817999be4SNeilBrown * So: regular IO calls 'wait_barrier'. When that returns there 64917999be4SNeilBrown * is no backgroup IO happening, It must arrange to call 65017999be4SNeilBrown * allow_barrier when it has finished its IO. 65117999be4SNeilBrown * backgroup IO calls must call raise_barrier. Once that returns 65217999be4SNeilBrown * there is no normal IO happeing. It must arrange to call 65317999be4SNeilBrown * lower_barrier when the particular background IO completes. 6541da177e4SLinus Torvalds */ 6551da177e4SLinus Torvalds #define RESYNC_DEPTH 32 6561da177e4SLinus Torvalds 65717999be4SNeilBrown static void raise_barrier(conf_t *conf) 6581da177e4SLinus Torvalds { 6591da177e4SLinus Torvalds spin_lock_irq(&conf->resync_lock); 6601da177e4SLinus Torvalds 66117999be4SNeilBrown /* Wait until no block IO is waiting */ 66217999be4SNeilBrown wait_event_lock_irq(conf->wait_barrier, !conf->nr_waiting, 66317999be4SNeilBrown conf->resync_lock, 66417999be4SNeilBrown raid1_unplug(conf->mddev->queue)); 66517999be4SNeilBrown 66617999be4SNeilBrown /* block any new IO from starting */ 66717999be4SNeilBrown conf->barrier++; 66817999be4SNeilBrown 66917999be4SNeilBrown /* No wait for all pending IO to complete */ 67017999be4SNeilBrown wait_event_lock_irq(conf->wait_barrier, 67117999be4SNeilBrown !conf->nr_pending && conf->barrier < RESYNC_DEPTH, 67217999be4SNeilBrown conf->resync_lock, 67317999be4SNeilBrown raid1_unplug(conf->mddev->queue)); 67417999be4SNeilBrown 6751da177e4SLinus Torvalds spin_unlock_irq(&conf->resync_lock); 6761da177e4SLinus Torvalds } 6771da177e4SLinus Torvalds 67817999be4SNeilBrown static void lower_barrier(conf_t *conf) 67917999be4SNeilBrown { 68017999be4SNeilBrown unsigned long flags; 681709ae487SNeilBrown BUG_ON(conf->barrier <= 0); 68217999be4SNeilBrown spin_lock_irqsave(&conf->resync_lock, flags); 68317999be4SNeilBrown conf->barrier--; 68417999be4SNeilBrown spin_unlock_irqrestore(&conf->resync_lock, flags); 68517999be4SNeilBrown wake_up(&conf->wait_barrier); 68617999be4SNeilBrown } 68717999be4SNeilBrown 68817999be4SNeilBrown static void wait_barrier(conf_t *conf) 68917999be4SNeilBrown { 69017999be4SNeilBrown spin_lock_irq(&conf->resync_lock); 69117999be4SNeilBrown if (conf->barrier) { 69217999be4SNeilBrown conf->nr_waiting++; 69317999be4SNeilBrown wait_event_lock_irq(conf->wait_barrier, !conf->barrier, 69417999be4SNeilBrown conf->resync_lock, 69517999be4SNeilBrown raid1_unplug(conf->mddev->queue)); 69617999be4SNeilBrown conf->nr_waiting--; 69717999be4SNeilBrown } 69817999be4SNeilBrown conf->nr_pending++; 69917999be4SNeilBrown spin_unlock_irq(&conf->resync_lock); 70017999be4SNeilBrown } 70117999be4SNeilBrown 70217999be4SNeilBrown static void allow_barrier(conf_t *conf) 70317999be4SNeilBrown { 70417999be4SNeilBrown unsigned long flags; 70517999be4SNeilBrown spin_lock_irqsave(&conf->resync_lock, flags); 70617999be4SNeilBrown conf->nr_pending--; 70717999be4SNeilBrown spin_unlock_irqrestore(&conf->resync_lock, flags); 70817999be4SNeilBrown wake_up(&conf->wait_barrier); 70917999be4SNeilBrown } 71017999be4SNeilBrown 711ddaf22abSNeilBrown static void freeze_array(conf_t *conf) 712ddaf22abSNeilBrown { 713ddaf22abSNeilBrown /* stop syncio and normal IO and wait for everything to 714ddaf22abSNeilBrown * go quite. 715ddaf22abSNeilBrown * We increment barrier and nr_waiting, and then 7161c830532SNeilBrown * wait until nr_pending match nr_queued+1 7171c830532SNeilBrown * This is called in the context of one normal IO request 7181c830532SNeilBrown * that has failed. Thus any sync request that might be pending 7191c830532SNeilBrown * will be blocked by nr_pending, and we need to wait for 7201c830532SNeilBrown * pending IO requests to complete or be queued for re-try. 7211c830532SNeilBrown * Thus the number queued (nr_queued) plus this request (1) 7221c830532SNeilBrown * must match the number of pending IOs (nr_pending) before 7231c830532SNeilBrown * we continue. 724ddaf22abSNeilBrown */ 725ddaf22abSNeilBrown spin_lock_irq(&conf->resync_lock); 726ddaf22abSNeilBrown conf->barrier++; 727ddaf22abSNeilBrown conf->nr_waiting++; 728ddaf22abSNeilBrown wait_event_lock_irq(conf->wait_barrier, 7291c830532SNeilBrown conf->nr_pending == conf->nr_queued+1, 730ddaf22abSNeilBrown conf->resync_lock, 731a35e63efSNeilBrown ({ flush_pending_writes(conf); 732a35e63efSNeilBrown raid1_unplug(conf->mddev->queue); })); 733ddaf22abSNeilBrown spin_unlock_irq(&conf->resync_lock); 734ddaf22abSNeilBrown } 735ddaf22abSNeilBrown static void unfreeze_array(conf_t *conf) 736ddaf22abSNeilBrown { 737ddaf22abSNeilBrown /* reverse the effect of the freeze */ 738ddaf22abSNeilBrown spin_lock_irq(&conf->resync_lock); 739ddaf22abSNeilBrown conf->barrier--; 740ddaf22abSNeilBrown conf->nr_waiting--; 741ddaf22abSNeilBrown wake_up(&conf->wait_barrier); 742ddaf22abSNeilBrown spin_unlock_irq(&conf->resync_lock); 743ddaf22abSNeilBrown } 744ddaf22abSNeilBrown 74517999be4SNeilBrown 7464b6d287fSNeilBrown /* duplicate the data pages for behind I/O */ 7474b6d287fSNeilBrown static struct page **alloc_behind_pages(struct bio *bio) 7484b6d287fSNeilBrown { 7494b6d287fSNeilBrown int i; 7504b6d287fSNeilBrown struct bio_vec *bvec; 7519ffae0cfSNeilBrown struct page **pages = kzalloc(bio->bi_vcnt * sizeof(struct page *), 7524b6d287fSNeilBrown GFP_NOIO); 7534b6d287fSNeilBrown if (unlikely(!pages)) 7544b6d287fSNeilBrown goto do_sync_io; 7554b6d287fSNeilBrown 7564b6d287fSNeilBrown bio_for_each_segment(bvec, bio, i) { 7574b6d287fSNeilBrown pages[i] = alloc_page(GFP_NOIO); 7584b6d287fSNeilBrown if (unlikely(!pages[i])) 7594b6d287fSNeilBrown goto do_sync_io; 7604b6d287fSNeilBrown memcpy(kmap(pages[i]) + bvec->bv_offset, 7614b6d287fSNeilBrown kmap(bvec->bv_page) + bvec->bv_offset, bvec->bv_len); 7624b6d287fSNeilBrown kunmap(pages[i]); 7634b6d287fSNeilBrown kunmap(bvec->bv_page); 7644b6d287fSNeilBrown } 7654b6d287fSNeilBrown 7664b6d287fSNeilBrown return pages; 7674b6d287fSNeilBrown 7684b6d287fSNeilBrown do_sync_io: 7694b6d287fSNeilBrown if (pages) 7704b6d287fSNeilBrown for (i = 0; i < bio->bi_vcnt && pages[i]; i++) 7712d1f3b5dSNeilBrown put_page(pages[i]); 7724b6d287fSNeilBrown kfree(pages); 7734b6d287fSNeilBrown PRINTK("%dB behind alloc failed, doing sync I/O\n", bio->bi_size); 7744b6d287fSNeilBrown return NULL; 7754b6d287fSNeilBrown } 7764b6d287fSNeilBrown 77721a52c6dSNeilBrown static int make_request(mddev_t *mddev, struct bio * bio) 7781da177e4SLinus Torvalds { 779070ec55dSNeilBrown conf_t *conf = mddev->private; 7801da177e4SLinus Torvalds mirror_info_t *mirror; 7811da177e4SLinus Torvalds r1bio_t *r1_bio; 7821da177e4SLinus Torvalds struct bio *read_bio; 783191ea9b2SNeilBrown int i, targets = 0, disks; 78484255d10SNeilBrown struct bitmap *bitmap; 785191ea9b2SNeilBrown unsigned long flags; 786191ea9b2SNeilBrown struct bio_list bl; 7874b6d287fSNeilBrown struct page **behind_pages = NULL; 788a362357bSJens Axboe const int rw = bio_data_dir(bio); 7891f98a13fSJens Axboe const bool do_sync = bio_rw_flagged(bio, BIO_RW_SYNCIO); 7901f98a13fSJens Axboe bool do_barriers; 7916bfe0b49SDan Williams mdk_rdev_t *blocked_rdev; 792191ea9b2SNeilBrown 7931da177e4SLinus Torvalds /* 7941da177e4SLinus Torvalds * Register the new request and wait if the reconstruction 7951da177e4SLinus Torvalds * thread has put up a bar for new requests. 7961da177e4SLinus Torvalds * Continue immediately if no resync is active currently. 79762de608dSNeilBrown * We test barriers_work *after* md_write_start as md_write_start 79862de608dSNeilBrown * may cause the first superblock write, and that will check out 79962de608dSNeilBrown * if barriers work. 8001da177e4SLinus Torvalds */ 80162de608dSNeilBrown 8023d310eb7SNeilBrown md_write_start(mddev, bio); /* wait on superblock update early */ 8033d310eb7SNeilBrown 8046eef4b21SNeilBrown if (bio_data_dir(bio) == WRITE && 8056eef4b21SNeilBrown bio->bi_sector + bio->bi_size/512 > mddev->suspend_lo && 8066eef4b21SNeilBrown bio->bi_sector < mddev->suspend_hi) { 8076eef4b21SNeilBrown /* As the suspend_* range is controlled by 8086eef4b21SNeilBrown * userspace, we want an interruptible 8096eef4b21SNeilBrown * wait. 8106eef4b21SNeilBrown */ 8116eef4b21SNeilBrown DEFINE_WAIT(w); 8126eef4b21SNeilBrown for (;;) { 8136eef4b21SNeilBrown flush_signals(current); 8146eef4b21SNeilBrown prepare_to_wait(&conf->wait_barrier, 8156eef4b21SNeilBrown &w, TASK_INTERRUPTIBLE); 8166eef4b21SNeilBrown if (bio->bi_sector + bio->bi_size/512 <= mddev->suspend_lo || 8176eef4b21SNeilBrown bio->bi_sector >= mddev->suspend_hi) 8186eef4b21SNeilBrown break; 8196eef4b21SNeilBrown schedule(); 8206eef4b21SNeilBrown } 8216eef4b21SNeilBrown finish_wait(&conf->wait_barrier, &w); 8226eef4b21SNeilBrown } 8231f98a13fSJens Axboe if (unlikely(!mddev->barriers_work && 8241f98a13fSJens Axboe bio_rw_flagged(bio, BIO_RW_BARRIER))) { 82562de608dSNeilBrown if (rw == WRITE) 82662de608dSNeilBrown md_write_end(mddev); 8276712ecf8SNeilBrown bio_endio(bio, -EOPNOTSUPP); 82862de608dSNeilBrown return 0; 82962de608dSNeilBrown } 83062de608dSNeilBrown 83117999be4SNeilBrown wait_barrier(conf); 8321da177e4SLinus Torvalds 83384255d10SNeilBrown bitmap = mddev->bitmap; 83484255d10SNeilBrown 8351da177e4SLinus Torvalds /* 8361da177e4SLinus Torvalds * make_request() can abort the operation when READA is being 8371da177e4SLinus Torvalds * used and no empty request is available. 8381da177e4SLinus Torvalds * 8391da177e4SLinus Torvalds */ 8401da177e4SLinus Torvalds r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO); 8411da177e4SLinus Torvalds 8421da177e4SLinus Torvalds r1_bio->master_bio = bio; 8431da177e4SLinus Torvalds r1_bio->sectors = bio->bi_size >> 9; 844191ea9b2SNeilBrown r1_bio->state = 0; 8451da177e4SLinus Torvalds r1_bio->mddev = mddev; 8461da177e4SLinus Torvalds r1_bio->sector = bio->bi_sector; 8471da177e4SLinus Torvalds 848a362357bSJens Axboe if (rw == READ) { 8491da177e4SLinus Torvalds /* 8501da177e4SLinus Torvalds * read balancing logic: 8511da177e4SLinus Torvalds */ 8521da177e4SLinus Torvalds int rdisk = read_balance(conf, r1_bio); 8531da177e4SLinus Torvalds 8541da177e4SLinus Torvalds if (rdisk < 0) { 8551da177e4SLinus Torvalds /* couldn't find anywhere to read from */ 8561da177e4SLinus Torvalds raid_end_bio_io(r1_bio); 8571da177e4SLinus Torvalds return 0; 8581da177e4SLinus Torvalds } 8591da177e4SLinus Torvalds mirror = conf->mirrors + rdisk; 8601da177e4SLinus Torvalds 861e555190dSNeilBrown if (test_bit(WriteMostly, &mirror->rdev->flags) && 862e555190dSNeilBrown bitmap) { 863e555190dSNeilBrown /* Reading from a write-mostly device must 864e555190dSNeilBrown * take care not to over-take any writes 865e555190dSNeilBrown * that are 'behind' 866e555190dSNeilBrown */ 867e555190dSNeilBrown wait_event(bitmap->behind_wait, 868e555190dSNeilBrown atomic_read(&bitmap->behind_writes) == 0); 869e555190dSNeilBrown } 8701da177e4SLinus Torvalds r1_bio->read_disk = rdisk; 8711da177e4SLinus Torvalds 8721da177e4SLinus Torvalds read_bio = bio_clone(bio, GFP_NOIO); 8731da177e4SLinus Torvalds 8741da177e4SLinus Torvalds r1_bio->bios[rdisk] = read_bio; 8751da177e4SLinus Torvalds 8761da177e4SLinus Torvalds read_bio->bi_sector = r1_bio->sector + mirror->rdev->data_offset; 8771da177e4SLinus Torvalds read_bio->bi_bdev = mirror->rdev->bdev; 8781da177e4SLinus Torvalds read_bio->bi_end_io = raid1_end_read_request; 8791ef04fefSDmitry Monakhov read_bio->bi_rw = READ | (do_sync << BIO_RW_SYNCIO); 8801da177e4SLinus Torvalds read_bio->bi_private = r1_bio; 8811da177e4SLinus Torvalds 8821da177e4SLinus Torvalds generic_make_request(read_bio); 8831da177e4SLinus Torvalds return 0; 8841da177e4SLinus Torvalds } 8851da177e4SLinus Torvalds 8861da177e4SLinus Torvalds /* 8871da177e4SLinus Torvalds * WRITE: 8881da177e4SLinus Torvalds */ 8891da177e4SLinus Torvalds /* first select target devices under spinlock and 8901da177e4SLinus Torvalds * inc refcount on their rdev. Record them by setting 8911da177e4SLinus Torvalds * bios[x] to bio 8921da177e4SLinus Torvalds */ 8931da177e4SLinus Torvalds disks = conf->raid_disks; 894191ea9b2SNeilBrown #if 0 895191ea9b2SNeilBrown { static int first=1; 896191ea9b2SNeilBrown if (first) printk("First Write sector %llu disks %d\n", 897191ea9b2SNeilBrown (unsigned long long)r1_bio->sector, disks); 898191ea9b2SNeilBrown first = 0; 899191ea9b2SNeilBrown } 900191ea9b2SNeilBrown #endif 9016bfe0b49SDan Williams retry_write: 9026bfe0b49SDan Williams blocked_rdev = NULL; 9031da177e4SLinus Torvalds rcu_read_lock(); 9041da177e4SLinus Torvalds for (i = 0; i < disks; i++) { 9056bfe0b49SDan Williams mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); 9066bfe0b49SDan Williams if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { 9076bfe0b49SDan Williams atomic_inc(&rdev->nr_pending); 9086bfe0b49SDan Williams blocked_rdev = rdev; 9096bfe0b49SDan Williams break; 9106bfe0b49SDan Williams } 9116bfe0b49SDan Williams if (rdev && !test_bit(Faulty, &rdev->flags)) { 9121da177e4SLinus Torvalds atomic_inc(&rdev->nr_pending); 913b2d444d7SNeilBrown if (test_bit(Faulty, &rdev->flags)) { 91403c902e1SNeilBrown rdev_dec_pending(rdev, mddev); 9151da177e4SLinus Torvalds r1_bio->bios[i] = NULL; 916964147d5SNeilBrown } else { 9171da177e4SLinus Torvalds r1_bio->bios[i] = bio; 918191ea9b2SNeilBrown targets++; 919964147d5SNeilBrown } 9201da177e4SLinus Torvalds } else 9211da177e4SLinus Torvalds r1_bio->bios[i] = NULL; 9221da177e4SLinus Torvalds } 9231da177e4SLinus Torvalds rcu_read_unlock(); 9241da177e4SLinus Torvalds 9256bfe0b49SDan Williams if (unlikely(blocked_rdev)) { 9266bfe0b49SDan Williams /* Wait for this device to become unblocked */ 9276bfe0b49SDan Williams int j; 9286bfe0b49SDan Williams 9296bfe0b49SDan Williams for (j = 0; j < i; j++) 9306bfe0b49SDan Williams if (r1_bio->bios[j]) 9316bfe0b49SDan Williams rdev_dec_pending(conf->mirrors[j].rdev, mddev); 9326bfe0b49SDan Williams 9336bfe0b49SDan Williams allow_barrier(conf); 9346bfe0b49SDan Williams md_wait_for_blocked_rdev(blocked_rdev, mddev); 9356bfe0b49SDan Williams wait_barrier(conf); 9366bfe0b49SDan Williams goto retry_write; 9376bfe0b49SDan Williams } 9386bfe0b49SDan Williams 9394b6d287fSNeilBrown BUG_ON(targets == 0); /* we never fail the last device */ 9404b6d287fSNeilBrown 941191ea9b2SNeilBrown if (targets < conf->raid_disks) { 942191ea9b2SNeilBrown /* array is degraded, we will not clear the bitmap 943191ea9b2SNeilBrown * on I/O completion (see raid1_end_write_request) */ 944191ea9b2SNeilBrown set_bit(R1BIO_Degraded, &r1_bio->state); 945191ea9b2SNeilBrown } 94606d91a5fSNeilBrown 947e555190dSNeilBrown /* do behind I/O ? 948e555190dSNeilBrown * Not if there are too many, or cannot allocate memory, 949e555190dSNeilBrown * or a reader on WriteMostly is waiting for behind writes 950e555190dSNeilBrown * to flush */ 9514b6d287fSNeilBrown if (bitmap && 95242a04b50SNeilBrown (atomic_read(&bitmap->behind_writes) 95342a04b50SNeilBrown < mddev->bitmap_info.max_write_behind) && 954e555190dSNeilBrown !waitqueue_active(&bitmap->behind_wait) && 9554b6d287fSNeilBrown (behind_pages = alloc_behind_pages(bio)) != NULL) 9564b6d287fSNeilBrown set_bit(R1BIO_BehindIO, &r1_bio->state); 9574b6d287fSNeilBrown 958191ea9b2SNeilBrown atomic_set(&r1_bio->remaining, 0); 9594b6d287fSNeilBrown atomic_set(&r1_bio->behind_remaining, 0); 960191ea9b2SNeilBrown 9611f98a13fSJens Axboe do_barriers = bio_rw_flagged(bio, BIO_RW_BARRIER); 962a9701a30SNeilBrown if (do_barriers) 963a9701a30SNeilBrown set_bit(R1BIO_Barrier, &r1_bio->state); 964a9701a30SNeilBrown 965191ea9b2SNeilBrown bio_list_init(&bl); 9661da177e4SLinus Torvalds for (i = 0; i < disks; i++) { 9671da177e4SLinus Torvalds struct bio *mbio; 9681da177e4SLinus Torvalds if (!r1_bio->bios[i]) 9691da177e4SLinus Torvalds continue; 9701da177e4SLinus Torvalds 9711da177e4SLinus Torvalds mbio = bio_clone(bio, GFP_NOIO); 9721da177e4SLinus Torvalds r1_bio->bios[i] = mbio; 9731da177e4SLinus Torvalds 9741da177e4SLinus Torvalds mbio->bi_sector = r1_bio->sector + conf->mirrors[i].rdev->data_offset; 9751da177e4SLinus Torvalds mbio->bi_bdev = conf->mirrors[i].rdev->bdev; 9761da177e4SLinus Torvalds mbio->bi_end_io = raid1_end_write_request; 9771ef04fefSDmitry Monakhov mbio->bi_rw = WRITE | (do_barriers << BIO_RW_BARRIER) | 9781ef04fefSDmitry Monakhov (do_sync << BIO_RW_SYNCIO); 9791da177e4SLinus Torvalds mbio->bi_private = r1_bio; 9801da177e4SLinus Torvalds 9814b6d287fSNeilBrown if (behind_pages) { 9824b6d287fSNeilBrown struct bio_vec *bvec; 9834b6d287fSNeilBrown int j; 9844b6d287fSNeilBrown 9854b6d287fSNeilBrown /* Yes, I really want the '__' version so that 9864b6d287fSNeilBrown * we clear any unused pointer in the io_vec, rather 9874b6d287fSNeilBrown * than leave them unchanged. This is important 9884b6d287fSNeilBrown * because when we come to free the pages, we won't 9894b6d287fSNeilBrown * know the originial bi_idx, so we just free 9904b6d287fSNeilBrown * them all 9914b6d287fSNeilBrown */ 9924b6d287fSNeilBrown __bio_for_each_segment(bvec, mbio, j, 0) 9934b6d287fSNeilBrown bvec->bv_page = behind_pages[j]; 9944b6d287fSNeilBrown if (test_bit(WriteMostly, &conf->mirrors[i].rdev->flags)) 9954b6d287fSNeilBrown atomic_inc(&r1_bio->behind_remaining); 9964b6d287fSNeilBrown } 9974b6d287fSNeilBrown 9981da177e4SLinus Torvalds atomic_inc(&r1_bio->remaining); 999191ea9b2SNeilBrown 1000191ea9b2SNeilBrown bio_list_add(&bl, mbio); 10011da177e4SLinus Torvalds } 10024b6d287fSNeilBrown kfree(behind_pages); /* the behind pages are attached to the bios now */ 10031da177e4SLinus Torvalds 10044b6d287fSNeilBrown bitmap_startwrite(bitmap, bio->bi_sector, r1_bio->sectors, 10054b6d287fSNeilBrown test_bit(R1BIO_BehindIO, &r1_bio->state)); 1006191ea9b2SNeilBrown spin_lock_irqsave(&conf->device_lock, flags); 1007191ea9b2SNeilBrown bio_list_merge(&conf->pending_bio_list, &bl); 1008191ea9b2SNeilBrown bio_list_init(&bl); 1009191ea9b2SNeilBrown 1010191ea9b2SNeilBrown blk_plug_device(mddev->queue); 1011191ea9b2SNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 1012191ea9b2SNeilBrown 1013a35e63efSNeilBrown /* In case raid1d snuck into freeze_array */ 1014a35e63efSNeilBrown wake_up(&conf->wait_barrier); 1015a35e63efSNeilBrown 1016e3881a68SLars Ellenberg if (do_sync) 1017e3881a68SLars Ellenberg md_wakeup_thread(mddev->thread); 1018191ea9b2SNeilBrown #if 0 1019191ea9b2SNeilBrown while ((bio = bio_list_pop(&bl)) != NULL) 1020191ea9b2SNeilBrown generic_make_request(bio); 1021191ea9b2SNeilBrown #endif 10221da177e4SLinus Torvalds 10231da177e4SLinus Torvalds return 0; 10241da177e4SLinus Torvalds } 10251da177e4SLinus Torvalds 10261da177e4SLinus Torvalds static void status(struct seq_file *seq, mddev_t *mddev) 10271da177e4SLinus Torvalds { 1028070ec55dSNeilBrown conf_t *conf = mddev->private; 10291da177e4SLinus Torvalds int i; 10301da177e4SLinus Torvalds 10311da177e4SLinus Torvalds seq_printf(seq, " [%d/%d] [", conf->raid_disks, 103211ce99e6SNeilBrown conf->raid_disks - mddev->degraded); 1033ddac7c7eSNeilBrown rcu_read_lock(); 1034ddac7c7eSNeilBrown for (i = 0; i < conf->raid_disks; i++) { 1035ddac7c7eSNeilBrown mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); 10361da177e4SLinus Torvalds seq_printf(seq, "%s", 1037ddac7c7eSNeilBrown rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_"); 1038ddac7c7eSNeilBrown } 1039ddac7c7eSNeilBrown rcu_read_unlock(); 10401da177e4SLinus Torvalds seq_printf(seq, "]"); 10411da177e4SLinus Torvalds } 10421da177e4SLinus Torvalds 10431da177e4SLinus Torvalds 10441da177e4SLinus Torvalds static void error(mddev_t *mddev, mdk_rdev_t *rdev) 10451da177e4SLinus Torvalds { 10461da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 1047070ec55dSNeilBrown conf_t *conf = mddev->private; 10481da177e4SLinus Torvalds 10491da177e4SLinus Torvalds /* 10501da177e4SLinus Torvalds * If it is not operational, then we have already marked it as dead 10511da177e4SLinus Torvalds * else if it is the last working disks, ignore the error, let the 10521da177e4SLinus Torvalds * next level up know. 10531da177e4SLinus Torvalds * else mark the drive as failed 10541da177e4SLinus Torvalds */ 1055b2d444d7SNeilBrown if (test_bit(In_sync, &rdev->flags) 10564044ba58SNeilBrown && (conf->raid_disks - mddev->degraded) == 1) { 10571da177e4SLinus Torvalds /* 10581da177e4SLinus Torvalds * Don't fail the drive, act as though we were just a 10594044ba58SNeilBrown * normal single drive. 10604044ba58SNeilBrown * However don't try a recovery from this drive as 10614044ba58SNeilBrown * it is very likely to fail. 10621da177e4SLinus Torvalds */ 10634044ba58SNeilBrown mddev->recovery_disabled = 1; 10641da177e4SLinus Torvalds return; 10654044ba58SNeilBrown } 1066c04be0aaSNeilBrown if (test_and_clear_bit(In_sync, &rdev->flags)) { 1067c04be0aaSNeilBrown unsigned long flags; 1068c04be0aaSNeilBrown spin_lock_irqsave(&conf->device_lock, flags); 10691da177e4SLinus Torvalds mddev->degraded++; 1070dd00a99eSNeilBrown set_bit(Faulty, &rdev->flags); 1071c04be0aaSNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 10721da177e4SLinus Torvalds /* 10731da177e4SLinus Torvalds * if recovery is running, make sure it aborts. 10741da177e4SLinus Torvalds */ 1075dfc70645SNeilBrown set_bit(MD_RECOVERY_INTR, &mddev->recovery); 1076dd00a99eSNeilBrown } else 1077b2d444d7SNeilBrown set_bit(Faulty, &rdev->flags); 1078850b2b42SNeilBrown set_bit(MD_CHANGE_DEVS, &mddev->flags); 10799dd1e2faSNeilBrown printk(KERN_ALERT "md/raid1:%s: Disk failure on %s, disabling device.\n" 10809dd1e2faSNeilBrown KERN_ALERT "md/raid1:%s: Operation continuing on %d devices.\n", 10819dd1e2faSNeilBrown mdname(mddev), bdevname(rdev->bdev, b), 10829dd1e2faSNeilBrown mdname(mddev), conf->raid_disks - mddev->degraded); 10831da177e4SLinus Torvalds } 10841da177e4SLinus Torvalds 10851da177e4SLinus Torvalds static void print_conf(conf_t *conf) 10861da177e4SLinus Torvalds { 10871da177e4SLinus Torvalds int i; 10881da177e4SLinus Torvalds 10899dd1e2faSNeilBrown printk(KERN_DEBUG "RAID1 conf printout:\n"); 10901da177e4SLinus Torvalds if (!conf) { 10919dd1e2faSNeilBrown printk(KERN_DEBUG "(!conf)\n"); 10921da177e4SLinus Torvalds return; 10931da177e4SLinus Torvalds } 10949dd1e2faSNeilBrown printk(KERN_DEBUG " --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded, 10951da177e4SLinus Torvalds conf->raid_disks); 10961da177e4SLinus Torvalds 1097ddac7c7eSNeilBrown rcu_read_lock(); 10981da177e4SLinus Torvalds for (i = 0; i < conf->raid_disks; i++) { 10991da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 1100ddac7c7eSNeilBrown mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); 1101ddac7c7eSNeilBrown if (rdev) 11029dd1e2faSNeilBrown printk(KERN_DEBUG " disk %d, wo:%d, o:%d, dev:%s\n", 1103ddac7c7eSNeilBrown i, !test_bit(In_sync, &rdev->flags), 1104ddac7c7eSNeilBrown !test_bit(Faulty, &rdev->flags), 1105ddac7c7eSNeilBrown bdevname(rdev->bdev,b)); 11061da177e4SLinus Torvalds } 1107ddac7c7eSNeilBrown rcu_read_unlock(); 11081da177e4SLinus Torvalds } 11091da177e4SLinus Torvalds 11101da177e4SLinus Torvalds static void close_sync(conf_t *conf) 11111da177e4SLinus Torvalds { 111217999be4SNeilBrown wait_barrier(conf); 111317999be4SNeilBrown allow_barrier(conf); 11141da177e4SLinus Torvalds 11151da177e4SLinus Torvalds mempool_destroy(conf->r1buf_pool); 11161da177e4SLinus Torvalds conf->r1buf_pool = NULL; 11171da177e4SLinus Torvalds } 11181da177e4SLinus Torvalds 11191da177e4SLinus Torvalds static int raid1_spare_active(mddev_t *mddev) 11201da177e4SLinus Torvalds { 11211da177e4SLinus Torvalds int i; 11221da177e4SLinus Torvalds conf_t *conf = mddev->private; 11231da177e4SLinus Torvalds 11241da177e4SLinus Torvalds /* 11251da177e4SLinus Torvalds * Find all failed disks within the RAID1 configuration 1126ddac7c7eSNeilBrown * and mark them readable. 1127ddac7c7eSNeilBrown * Called under mddev lock, so rcu protection not needed. 11281da177e4SLinus Torvalds */ 11291da177e4SLinus Torvalds for (i = 0; i < conf->raid_disks; i++) { 1130ddac7c7eSNeilBrown mdk_rdev_t *rdev = conf->mirrors[i].rdev; 1131ddac7c7eSNeilBrown if (rdev 1132ddac7c7eSNeilBrown && !test_bit(Faulty, &rdev->flags) 1133c04be0aaSNeilBrown && !test_and_set_bit(In_sync, &rdev->flags)) { 1134c04be0aaSNeilBrown unsigned long flags; 1135c04be0aaSNeilBrown spin_lock_irqsave(&conf->device_lock, flags); 11361da177e4SLinus Torvalds mddev->degraded--; 1137c04be0aaSNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 11381da177e4SLinus Torvalds } 11391da177e4SLinus Torvalds } 11401da177e4SLinus Torvalds 11411da177e4SLinus Torvalds print_conf(conf); 11421da177e4SLinus Torvalds return 0; 11431da177e4SLinus Torvalds } 11441da177e4SLinus Torvalds 11451da177e4SLinus Torvalds 11461da177e4SLinus Torvalds static int raid1_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) 11471da177e4SLinus Torvalds { 11481da177e4SLinus Torvalds conf_t *conf = mddev->private; 1149199050eaSNeil Brown int err = -EEXIST; 115041158c7eSNeilBrown int mirror = 0; 11511da177e4SLinus Torvalds mirror_info_t *p; 11526c2fce2eSNeil Brown int first = 0; 11536c2fce2eSNeil Brown int last = mddev->raid_disks - 1; 11541da177e4SLinus Torvalds 11556c2fce2eSNeil Brown if (rdev->raid_disk >= 0) 11566c2fce2eSNeil Brown first = last = rdev->raid_disk; 11576c2fce2eSNeil Brown 11586c2fce2eSNeil Brown for (mirror = first; mirror <= last; mirror++) 11591da177e4SLinus Torvalds if ( !(p=conf->mirrors+mirror)->rdev) { 11601da177e4SLinus Torvalds 11618f6c2e4bSMartin K. Petersen disk_stack_limits(mddev->gendisk, rdev->bdev, 11628f6c2e4bSMartin K. Petersen rdev->data_offset << 9); 1163627a2d3cSNeilBrown /* as we don't honour merge_bvec_fn, we must 1164627a2d3cSNeilBrown * never risk violating it, so limit 1165627a2d3cSNeilBrown * ->max_segments to one lying with a single 1166627a2d3cSNeilBrown * page, as a one page request is never in 1167627a2d3cSNeilBrown * violation. 11681da177e4SLinus Torvalds */ 1169627a2d3cSNeilBrown if (rdev->bdev->bd_disk->queue->merge_bvec_fn) { 1170627a2d3cSNeilBrown blk_queue_max_segments(mddev->queue, 1); 1171627a2d3cSNeilBrown blk_queue_segment_boundary(mddev->queue, 1172627a2d3cSNeilBrown PAGE_CACHE_SIZE - 1); 1173627a2d3cSNeilBrown } 11741da177e4SLinus Torvalds 11751da177e4SLinus Torvalds p->head_position = 0; 11761da177e4SLinus Torvalds rdev->raid_disk = mirror; 1177199050eaSNeil Brown err = 0; 11786aea114aSNeilBrown /* As all devices are equivalent, we don't need a full recovery 11796aea114aSNeilBrown * if this was recently any drive of the array 11806aea114aSNeilBrown */ 11816aea114aSNeilBrown if (rdev->saved_raid_disk < 0) 118241158c7eSNeilBrown conf->fullsync = 1; 1183d6065f7bSSuzanne Wood rcu_assign_pointer(p->rdev, rdev); 11841da177e4SLinus Torvalds break; 11851da177e4SLinus Torvalds } 1186ac5e7113SAndre Noll md_integrity_add_rdev(rdev, mddev); 11871da177e4SLinus Torvalds print_conf(conf); 1188199050eaSNeil Brown return err; 11891da177e4SLinus Torvalds } 11901da177e4SLinus Torvalds 11911da177e4SLinus Torvalds static int raid1_remove_disk(mddev_t *mddev, int number) 11921da177e4SLinus Torvalds { 11931da177e4SLinus Torvalds conf_t *conf = mddev->private; 11941da177e4SLinus Torvalds int err = 0; 11951da177e4SLinus Torvalds mdk_rdev_t *rdev; 11961da177e4SLinus Torvalds mirror_info_t *p = conf->mirrors+ number; 11971da177e4SLinus Torvalds 11981da177e4SLinus Torvalds print_conf(conf); 11991da177e4SLinus Torvalds rdev = p->rdev; 12001da177e4SLinus Torvalds if (rdev) { 1201b2d444d7SNeilBrown if (test_bit(In_sync, &rdev->flags) || 12021da177e4SLinus Torvalds atomic_read(&rdev->nr_pending)) { 12031da177e4SLinus Torvalds err = -EBUSY; 12041da177e4SLinus Torvalds goto abort; 12051da177e4SLinus Torvalds } 1206dfc70645SNeilBrown /* Only remove non-faulty devices is recovery 1207dfc70645SNeilBrown * is not possible. 1208dfc70645SNeilBrown */ 1209dfc70645SNeilBrown if (!test_bit(Faulty, &rdev->flags) && 1210dfc70645SNeilBrown mddev->degraded < conf->raid_disks) { 1211dfc70645SNeilBrown err = -EBUSY; 1212dfc70645SNeilBrown goto abort; 1213dfc70645SNeilBrown } 12141da177e4SLinus Torvalds p->rdev = NULL; 1215fbd568a3SPaul E. McKenney synchronize_rcu(); 12161da177e4SLinus Torvalds if (atomic_read(&rdev->nr_pending)) { 12171da177e4SLinus Torvalds /* lost the race, try later */ 12181da177e4SLinus Torvalds err = -EBUSY; 12191da177e4SLinus Torvalds p->rdev = rdev; 1220ac5e7113SAndre Noll goto abort; 12211da177e4SLinus Torvalds } 1222ac5e7113SAndre Noll md_integrity_register(mddev); 12231da177e4SLinus Torvalds } 12241da177e4SLinus Torvalds abort: 12251da177e4SLinus Torvalds 12261da177e4SLinus Torvalds print_conf(conf); 12271da177e4SLinus Torvalds return err; 12281da177e4SLinus Torvalds } 12291da177e4SLinus Torvalds 12301da177e4SLinus Torvalds 12316712ecf8SNeilBrown static void end_sync_read(struct bio *bio, int error) 12321da177e4SLinus Torvalds { 12337b92813cSH Hartley Sweeten r1bio_t *r1_bio = bio->bi_private; 1234d11c171eSNeilBrown int i; 12351da177e4SLinus Torvalds 1236d11c171eSNeilBrown for (i=r1_bio->mddev->raid_disks; i--; ) 1237d11c171eSNeilBrown if (r1_bio->bios[i] == bio) 1238d11c171eSNeilBrown break; 1239d11c171eSNeilBrown BUG_ON(i < 0); 1240d11c171eSNeilBrown update_head_pos(i, r1_bio); 12411da177e4SLinus Torvalds /* 12421da177e4SLinus Torvalds * we have read a block, now it needs to be re-written, 12431da177e4SLinus Torvalds * or re-read if the read failed. 12441da177e4SLinus Torvalds * We don't do much here, just schedule handling by raid1d 12451da177e4SLinus Torvalds */ 124669382e85SNeilBrown if (test_bit(BIO_UPTODATE, &bio->bi_flags)) 12471da177e4SLinus Torvalds set_bit(R1BIO_Uptodate, &r1_bio->state); 1248d11c171eSNeilBrown 1249d11c171eSNeilBrown if (atomic_dec_and_test(&r1_bio->remaining)) 12501da177e4SLinus Torvalds reschedule_retry(r1_bio); 12511da177e4SLinus Torvalds } 12521da177e4SLinus Torvalds 12536712ecf8SNeilBrown static void end_sync_write(struct bio *bio, int error) 12541da177e4SLinus Torvalds { 12551da177e4SLinus Torvalds int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); 12567b92813cSH Hartley Sweeten r1bio_t *r1_bio = bio->bi_private; 12571da177e4SLinus Torvalds mddev_t *mddev = r1_bio->mddev; 1258070ec55dSNeilBrown conf_t *conf = mddev->private; 12591da177e4SLinus Torvalds int i; 12601da177e4SLinus Torvalds int mirror=0; 12611da177e4SLinus Torvalds 12621da177e4SLinus Torvalds for (i = 0; i < conf->raid_disks; i++) 12631da177e4SLinus Torvalds if (r1_bio->bios[i] == bio) { 12641da177e4SLinus Torvalds mirror = i; 12651da177e4SLinus Torvalds break; 12661da177e4SLinus Torvalds } 12676b1117d5SNeilBrown if (!uptodate) { 12686b1117d5SNeilBrown int sync_blocks = 0; 12696b1117d5SNeilBrown sector_t s = r1_bio->sector; 12706b1117d5SNeilBrown long sectors_to_go = r1_bio->sectors; 12716b1117d5SNeilBrown /* make sure these bits doesn't get cleared. */ 12726b1117d5SNeilBrown do { 12735e3db645SNeilBrown bitmap_end_sync(mddev->bitmap, s, 12746b1117d5SNeilBrown &sync_blocks, 1); 12756b1117d5SNeilBrown s += sync_blocks; 12766b1117d5SNeilBrown sectors_to_go -= sync_blocks; 12776b1117d5SNeilBrown } while (sectors_to_go > 0); 12781da177e4SLinus Torvalds md_error(mddev, conf->mirrors[mirror].rdev); 12796b1117d5SNeilBrown } 1280e3b9703eSNeilBrown 12811da177e4SLinus Torvalds update_head_pos(mirror, r1_bio); 12821da177e4SLinus Torvalds 12831da177e4SLinus Torvalds if (atomic_dec_and_test(&r1_bio->remaining)) { 128473d5c38aSNeilBrown sector_t s = r1_bio->sectors; 12851da177e4SLinus Torvalds put_buf(r1_bio); 128673d5c38aSNeilBrown md_done_sync(mddev, s, uptodate); 12871da177e4SLinus Torvalds } 12881da177e4SLinus Torvalds } 12891da177e4SLinus Torvalds 12901da177e4SLinus Torvalds static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) 12911da177e4SLinus Torvalds { 1292070ec55dSNeilBrown conf_t *conf = mddev->private; 12931da177e4SLinus Torvalds int i; 12941da177e4SLinus Torvalds int disks = conf->raid_disks; 12951da177e4SLinus Torvalds struct bio *bio, *wbio; 12961da177e4SLinus Torvalds 12971da177e4SLinus Torvalds bio = r1_bio->bios[r1_bio->read_disk]; 12981da177e4SLinus Torvalds 129969382e85SNeilBrown 1300d11c171eSNeilBrown if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { 1301d11c171eSNeilBrown /* We have read all readable devices. If we haven't 1302d11c171eSNeilBrown * got the block, then there is no hope left. 1303d11c171eSNeilBrown * If we have, then we want to do a comparison 1304d11c171eSNeilBrown * and skip the write if everything is the same. 1305d11c171eSNeilBrown * If any blocks failed to read, then we need to 1306d11c171eSNeilBrown * attempt an over-write 13071da177e4SLinus Torvalds */ 1308d11c171eSNeilBrown int primary; 1309d11c171eSNeilBrown if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) { 1310d11c171eSNeilBrown for (i=0; i<mddev->raid_disks; i++) 1311d11c171eSNeilBrown if (r1_bio->bios[i]->bi_end_io == end_sync_read) 1312d11c171eSNeilBrown md_error(mddev, conf->mirrors[i].rdev); 1313d11c171eSNeilBrown 1314d11c171eSNeilBrown md_done_sync(mddev, r1_bio->sectors, 1); 1315d11c171eSNeilBrown put_buf(r1_bio); 1316d11c171eSNeilBrown return; 1317d11c171eSNeilBrown } 1318d11c171eSNeilBrown for (primary=0; primary<mddev->raid_disks; primary++) 1319d11c171eSNeilBrown if (r1_bio->bios[primary]->bi_end_io == end_sync_read && 1320d11c171eSNeilBrown test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) { 1321d11c171eSNeilBrown r1_bio->bios[primary]->bi_end_io = NULL; 132203c902e1SNeilBrown rdev_dec_pending(conf->mirrors[primary].rdev, mddev); 1323d11c171eSNeilBrown break; 1324d11c171eSNeilBrown } 1325d11c171eSNeilBrown r1_bio->read_disk = primary; 1326d11c171eSNeilBrown for (i=0; i<mddev->raid_disks; i++) 1327ed456662SMike Accetta if (r1_bio->bios[i]->bi_end_io == end_sync_read) { 1328d11c171eSNeilBrown int j; 1329d11c171eSNeilBrown int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9); 1330d11c171eSNeilBrown struct bio *pbio = r1_bio->bios[primary]; 1331d11c171eSNeilBrown struct bio *sbio = r1_bio->bios[i]; 1332ed456662SMike Accetta 1333ed456662SMike Accetta if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) { 1334ed456662SMike Accetta for (j = vcnt; j-- ; ) { 1335ed456662SMike Accetta struct page *p, *s; 1336ed456662SMike Accetta p = pbio->bi_io_vec[j].bv_page; 1337ed456662SMike Accetta s = sbio->bi_io_vec[j].bv_page; 1338ed456662SMike Accetta if (memcmp(page_address(p), 1339ed456662SMike Accetta page_address(s), 1340d11c171eSNeilBrown PAGE_SIZE)) 1341d11c171eSNeilBrown break; 1342ed456662SMike Accetta } 1343ed456662SMike Accetta } else 1344ed456662SMike Accetta j = 0; 1345d11c171eSNeilBrown if (j >= 0) 1346d11c171eSNeilBrown mddev->resync_mismatches += r1_bio->sectors; 1347cf7a4416SNeilBrown if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery) 1348cf7a4416SNeilBrown && test_bit(BIO_UPTODATE, &sbio->bi_flags))) { 1349d11c171eSNeilBrown sbio->bi_end_io = NULL; 135003c902e1SNeilBrown rdev_dec_pending(conf->mirrors[i].rdev, mddev); 135103c902e1SNeilBrown } else { 1352d11c171eSNeilBrown /* fixup the bio for reuse */ 1353698b18c1SNeilBrown int size; 1354d11c171eSNeilBrown sbio->bi_vcnt = vcnt; 1355d11c171eSNeilBrown sbio->bi_size = r1_bio->sectors << 9; 1356d11c171eSNeilBrown sbio->bi_idx = 0; 1357d11c171eSNeilBrown sbio->bi_phys_segments = 0; 1358d11c171eSNeilBrown sbio->bi_flags &= ~(BIO_POOL_MASK - 1); 1359d11c171eSNeilBrown sbio->bi_flags |= 1 << BIO_UPTODATE; 1360d11c171eSNeilBrown sbio->bi_next = NULL; 1361d11c171eSNeilBrown sbio->bi_sector = r1_bio->sector + 1362d11c171eSNeilBrown conf->mirrors[i].rdev->data_offset; 1363d11c171eSNeilBrown sbio->bi_bdev = conf->mirrors[i].rdev->bdev; 1364698b18c1SNeilBrown size = sbio->bi_size; 1365698b18c1SNeilBrown for (j = 0; j < vcnt ; j++) { 1366698b18c1SNeilBrown struct bio_vec *bi; 1367698b18c1SNeilBrown bi = &sbio->bi_io_vec[j]; 1368698b18c1SNeilBrown bi->bv_offset = 0; 1369698b18c1SNeilBrown if (size > PAGE_SIZE) 1370698b18c1SNeilBrown bi->bv_len = PAGE_SIZE; 1371698b18c1SNeilBrown else 1372698b18c1SNeilBrown bi->bv_len = size; 1373698b18c1SNeilBrown size -= PAGE_SIZE; 1374698b18c1SNeilBrown memcpy(page_address(bi->bv_page), 13753eda22d1SNeilBrown page_address(pbio->bi_io_vec[j].bv_page), 13763eda22d1SNeilBrown PAGE_SIZE); 1377698b18c1SNeilBrown } 13783eda22d1SNeilBrown 1379d11c171eSNeilBrown } 1380d11c171eSNeilBrown } 1381d11c171eSNeilBrown } 13821da177e4SLinus Torvalds if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) { 138369382e85SNeilBrown /* ouch - failed to read all of that. 138469382e85SNeilBrown * Try some synchronous reads of other devices to get 138569382e85SNeilBrown * good data, much like with normal read errors. Only 1386ddac7c7eSNeilBrown * read into the pages we already have so we don't 138769382e85SNeilBrown * need to re-issue the read request. 138869382e85SNeilBrown * We don't need to freeze the array, because being in an 138969382e85SNeilBrown * active sync request, there is no normal IO, and 139069382e85SNeilBrown * no overlapping syncs. 13911da177e4SLinus Torvalds */ 139269382e85SNeilBrown sector_t sect = r1_bio->sector; 139369382e85SNeilBrown int sectors = r1_bio->sectors; 139469382e85SNeilBrown int idx = 0; 139569382e85SNeilBrown 139669382e85SNeilBrown while(sectors) { 139769382e85SNeilBrown int s = sectors; 139869382e85SNeilBrown int d = r1_bio->read_disk; 139969382e85SNeilBrown int success = 0; 140069382e85SNeilBrown mdk_rdev_t *rdev; 140169382e85SNeilBrown 140269382e85SNeilBrown if (s > (PAGE_SIZE>>9)) 140369382e85SNeilBrown s = PAGE_SIZE >> 9; 140469382e85SNeilBrown do { 140569382e85SNeilBrown if (r1_bio->bios[d]->bi_end_io == end_sync_read) { 1406ddac7c7eSNeilBrown /* No rcu protection needed here devices 1407ddac7c7eSNeilBrown * can only be removed when no resync is 1408ddac7c7eSNeilBrown * active, and resync is currently active 1409ddac7c7eSNeilBrown */ 141069382e85SNeilBrown rdev = conf->mirrors[d].rdev; 141169382e85SNeilBrown if (sync_page_io(rdev->bdev, 141269382e85SNeilBrown sect + rdev->data_offset, 141369382e85SNeilBrown s<<9, 141469382e85SNeilBrown bio->bi_io_vec[idx].bv_page, 141569382e85SNeilBrown READ)) { 141669382e85SNeilBrown success = 1; 141769382e85SNeilBrown break; 141869382e85SNeilBrown } 141969382e85SNeilBrown } 142069382e85SNeilBrown d++; 142169382e85SNeilBrown if (d == conf->raid_disks) 142269382e85SNeilBrown d = 0; 142369382e85SNeilBrown } while (!success && d != r1_bio->read_disk); 142469382e85SNeilBrown 142569382e85SNeilBrown if (success) { 1426097426f6SNeilBrown int start = d; 142769382e85SNeilBrown /* write it back and re-read */ 142869382e85SNeilBrown set_bit(R1BIO_Uptodate, &r1_bio->state); 142969382e85SNeilBrown while (d != r1_bio->read_disk) { 143069382e85SNeilBrown if (d == 0) 143169382e85SNeilBrown d = conf->raid_disks; 143269382e85SNeilBrown d--; 143369382e85SNeilBrown if (r1_bio->bios[d]->bi_end_io != end_sync_read) 143469382e85SNeilBrown continue; 143569382e85SNeilBrown rdev = conf->mirrors[d].rdev; 14364dbcdc75SNeilBrown atomic_add(s, &rdev->corrected_errors); 143769382e85SNeilBrown if (sync_page_io(rdev->bdev, 143869382e85SNeilBrown sect + rdev->data_offset, 143969382e85SNeilBrown s<<9, 144069382e85SNeilBrown bio->bi_io_vec[idx].bv_page, 1441097426f6SNeilBrown WRITE) == 0) 1442097426f6SNeilBrown md_error(mddev, rdev); 1443097426f6SNeilBrown } 1444097426f6SNeilBrown d = start; 1445097426f6SNeilBrown while (d != r1_bio->read_disk) { 1446097426f6SNeilBrown if (d == 0) 1447097426f6SNeilBrown d = conf->raid_disks; 1448097426f6SNeilBrown d--; 1449097426f6SNeilBrown if (r1_bio->bios[d]->bi_end_io != end_sync_read) 1450097426f6SNeilBrown continue; 1451097426f6SNeilBrown rdev = conf->mirrors[d].rdev; 1452097426f6SNeilBrown if (sync_page_io(rdev->bdev, 145369382e85SNeilBrown sect + rdev->data_offset, 145469382e85SNeilBrown s<<9, 145569382e85SNeilBrown bio->bi_io_vec[idx].bv_page, 1456097426f6SNeilBrown READ) == 0) 145769382e85SNeilBrown md_error(mddev, rdev); 145869382e85SNeilBrown } 145969382e85SNeilBrown } else { 14601da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 146169382e85SNeilBrown /* Cannot read from anywhere, array is toast */ 146269382e85SNeilBrown md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev); 14639dd1e2faSNeilBrown printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O read error" 14641da177e4SLinus Torvalds " for block %llu\n", 14659dd1e2faSNeilBrown mdname(mddev), 14661da177e4SLinus Torvalds bdevname(bio->bi_bdev, b), 14671da177e4SLinus Torvalds (unsigned long long)r1_bio->sector); 14681da177e4SLinus Torvalds md_done_sync(mddev, r1_bio->sectors, 0); 14691da177e4SLinus Torvalds put_buf(r1_bio); 14701da177e4SLinus Torvalds return; 14711da177e4SLinus Torvalds } 147269382e85SNeilBrown sectors -= s; 147369382e85SNeilBrown sect += s; 147469382e85SNeilBrown idx ++; 147569382e85SNeilBrown } 147669382e85SNeilBrown } 1477d11c171eSNeilBrown 1478d11c171eSNeilBrown /* 1479d11c171eSNeilBrown * schedule writes 1480d11c171eSNeilBrown */ 14811da177e4SLinus Torvalds atomic_set(&r1_bio->remaining, 1); 14821da177e4SLinus Torvalds for (i = 0; i < disks ; i++) { 14831da177e4SLinus Torvalds wbio = r1_bio->bios[i]; 14843e198f78SNeilBrown if (wbio->bi_end_io == NULL || 14853e198f78SNeilBrown (wbio->bi_end_io == end_sync_read && 14863e198f78SNeilBrown (i == r1_bio->read_disk || 14873e198f78SNeilBrown !test_bit(MD_RECOVERY_SYNC, &mddev->recovery)))) 14881da177e4SLinus Torvalds continue; 14891da177e4SLinus Torvalds 14903e198f78SNeilBrown wbio->bi_rw = WRITE; 14913e198f78SNeilBrown wbio->bi_end_io = end_sync_write; 14921da177e4SLinus Torvalds atomic_inc(&r1_bio->remaining); 14931da177e4SLinus Torvalds md_sync_acct(conf->mirrors[i].rdev->bdev, wbio->bi_size >> 9); 1494191ea9b2SNeilBrown 14951da177e4SLinus Torvalds generic_make_request(wbio); 14961da177e4SLinus Torvalds } 14971da177e4SLinus Torvalds 14981da177e4SLinus Torvalds if (atomic_dec_and_test(&r1_bio->remaining)) { 1499191ea9b2SNeilBrown /* if we're here, all write(s) have completed, so clean up */ 15001da177e4SLinus Torvalds md_done_sync(mddev, r1_bio->sectors, 1); 15011da177e4SLinus Torvalds put_buf(r1_bio); 15021da177e4SLinus Torvalds } 15031da177e4SLinus Torvalds } 15041da177e4SLinus Torvalds 15051da177e4SLinus Torvalds /* 15061da177e4SLinus Torvalds * This is a kernel thread which: 15071da177e4SLinus Torvalds * 15081da177e4SLinus Torvalds * 1. Retries failed read operations on working mirrors. 15091da177e4SLinus Torvalds * 2. Updates the raid superblock when problems encounter. 15101da177e4SLinus Torvalds * 3. Performs writes following reads for array syncronising. 15111da177e4SLinus Torvalds */ 15121da177e4SLinus Torvalds 1513867868fbSNeilBrown static void fix_read_error(conf_t *conf, int read_disk, 1514867868fbSNeilBrown sector_t sect, int sectors) 1515867868fbSNeilBrown { 1516867868fbSNeilBrown mddev_t *mddev = conf->mddev; 1517867868fbSNeilBrown while(sectors) { 1518867868fbSNeilBrown int s = sectors; 1519867868fbSNeilBrown int d = read_disk; 1520867868fbSNeilBrown int success = 0; 1521867868fbSNeilBrown int start; 1522867868fbSNeilBrown mdk_rdev_t *rdev; 1523867868fbSNeilBrown 1524867868fbSNeilBrown if (s > (PAGE_SIZE>>9)) 1525867868fbSNeilBrown s = PAGE_SIZE >> 9; 1526867868fbSNeilBrown 1527867868fbSNeilBrown do { 1528867868fbSNeilBrown /* Note: no rcu protection needed here 1529867868fbSNeilBrown * as this is synchronous in the raid1d thread 1530867868fbSNeilBrown * which is the thread that might remove 1531867868fbSNeilBrown * a device. If raid1d ever becomes multi-threaded.... 1532867868fbSNeilBrown */ 1533867868fbSNeilBrown rdev = conf->mirrors[d].rdev; 1534867868fbSNeilBrown if (rdev && 1535867868fbSNeilBrown test_bit(In_sync, &rdev->flags) && 1536867868fbSNeilBrown sync_page_io(rdev->bdev, 1537867868fbSNeilBrown sect + rdev->data_offset, 1538867868fbSNeilBrown s<<9, 1539867868fbSNeilBrown conf->tmppage, READ)) 1540867868fbSNeilBrown success = 1; 1541867868fbSNeilBrown else { 1542867868fbSNeilBrown d++; 1543867868fbSNeilBrown if (d == conf->raid_disks) 1544867868fbSNeilBrown d = 0; 1545867868fbSNeilBrown } 1546867868fbSNeilBrown } while (!success && d != read_disk); 1547867868fbSNeilBrown 1548867868fbSNeilBrown if (!success) { 1549867868fbSNeilBrown /* Cannot read from anywhere -- bye bye array */ 1550867868fbSNeilBrown md_error(mddev, conf->mirrors[read_disk].rdev); 1551867868fbSNeilBrown break; 1552867868fbSNeilBrown } 1553867868fbSNeilBrown /* write it back and re-read */ 1554867868fbSNeilBrown start = d; 1555867868fbSNeilBrown while (d != read_disk) { 1556867868fbSNeilBrown if (d==0) 1557867868fbSNeilBrown d = conf->raid_disks; 1558867868fbSNeilBrown d--; 1559867868fbSNeilBrown rdev = conf->mirrors[d].rdev; 1560867868fbSNeilBrown if (rdev && 1561867868fbSNeilBrown test_bit(In_sync, &rdev->flags)) { 1562867868fbSNeilBrown if (sync_page_io(rdev->bdev, 1563867868fbSNeilBrown sect + rdev->data_offset, 1564867868fbSNeilBrown s<<9, conf->tmppage, WRITE) 1565867868fbSNeilBrown == 0) 1566867868fbSNeilBrown /* Well, this device is dead */ 1567867868fbSNeilBrown md_error(mddev, rdev); 1568867868fbSNeilBrown } 1569867868fbSNeilBrown } 1570867868fbSNeilBrown d = start; 1571867868fbSNeilBrown while (d != read_disk) { 1572867868fbSNeilBrown char b[BDEVNAME_SIZE]; 1573867868fbSNeilBrown if (d==0) 1574867868fbSNeilBrown d = conf->raid_disks; 1575867868fbSNeilBrown d--; 1576867868fbSNeilBrown rdev = conf->mirrors[d].rdev; 1577867868fbSNeilBrown if (rdev && 1578867868fbSNeilBrown test_bit(In_sync, &rdev->flags)) { 1579867868fbSNeilBrown if (sync_page_io(rdev->bdev, 1580867868fbSNeilBrown sect + rdev->data_offset, 1581867868fbSNeilBrown s<<9, conf->tmppage, READ) 1582867868fbSNeilBrown == 0) 1583867868fbSNeilBrown /* Well, this device is dead */ 1584867868fbSNeilBrown md_error(mddev, rdev); 1585867868fbSNeilBrown else { 1586867868fbSNeilBrown atomic_add(s, &rdev->corrected_errors); 1587867868fbSNeilBrown printk(KERN_INFO 15889dd1e2faSNeilBrown "md/raid1:%s: read error corrected " 1589867868fbSNeilBrown "(%d sectors at %llu on %s)\n", 1590867868fbSNeilBrown mdname(mddev), s, 1591969b755aSRandy Dunlap (unsigned long long)(sect + 1592969b755aSRandy Dunlap rdev->data_offset), 1593867868fbSNeilBrown bdevname(rdev->bdev, b)); 1594867868fbSNeilBrown } 1595867868fbSNeilBrown } 1596867868fbSNeilBrown } 1597867868fbSNeilBrown sectors -= s; 1598867868fbSNeilBrown sect += s; 1599867868fbSNeilBrown } 1600867868fbSNeilBrown } 1601867868fbSNeilBrown 16021da177e4SLinus Torvalds static void raid1d(mddev_t *mddev) 16031da177e4SLinus Torvalds { 16041da177e4SLinus Torvalds r1bio_t *r1_bio; 16051da177e4SLinus Torvalds struct bio *bio; 16061da177e4SLinus Torvalds unsigned long flags; 1607070ec55dSNeilBrown conf_t *conf = mddev->private; 16081da177e4SLinus Torvalds struct list_head *head = &conf->retry_list; 16091da177e4SLinus Torvalds int unplug=0; 16101da177e4SLinus Torvalds mdk_rdev_t *rdev; 16111da177e4SLinus Torvalds 16121da177e4SLinus Torvalds md_check_recovery(mddev); 16131da177e4SLinus Torvalds 16141da177e4SLinus Torvalds for (;;) { 16151da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 1616a35e63efSNeilBrown 1617a35e63efSNeilBrown unplug += flush_pending_writes(conf); 1618a35e63efSNeilBrown 16191da177e4SLinus Torvalds spin_lock_irqsave(&conf->device_lock, flags); 1620a35e63efSNeilBrown if (list_empty(head)) { 1621191ea9b2SNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 16221da177e4SLinus Torvalds break; 1623a35e63efSNeilBrown } 16241da177e4SLinus Torvalds r1_bio = list_entry(head->prev, r1bio_t, retry_list); 16251da177e4SLinus Torvalds list_del(head->prev); 1626ddaf22abSNeilBrown conf->nr_queued--; 16271da177e4SLinus Torvalds spin_unlock_irqrestore(&conf->device_lock, flags); 16281da177e4SLinus Torvalds 16291da177e4SLinus Torvalds mddev = r1_bio->mddev; 1630070ec55dSNeilBrown conf = mddev->private; 16311da177e4SLinus Torvalds if (test_bit(R1BIO_IsSync, &r1_bio->state)) { 16321da177e4SLinus Torvalds sync_request_write(mddev, r1_bio); 16331da177e4SLinus Torvalds unplug = 1; 1634a9701a30SNeilBrown } else if (test_bit(R1BIO_BarrierRetry, &r1_bio->state)) { 1635a9701a30SNeilBrown /* some requests in the r1bio were BIO_RW_BARRIER 1636bea27718SNeilBrown * requests which failed with -EOPNOTSUPP. Hohumm.. 1637a9701a30SNeilBrown * Better resubmit without the barrier. 1638a9701a30SNeilBrown * We know which devices to resubmit for, because 1639a9701a30SNeilBrown * all others have had their bios[] entry cleared. 16405e7dd2abSNeilBrown * We already have a nr_pending reference on these rdevs. 1641a9701a30SNeilBrown */ 1642a9701a30SNeilBrown int i; 16431f98a13fSJens Axboe const bool do_sync = bio_rw_flagged(r1_bio->master_bio, BIO_RW_SYNCIO); 1644a9701a30SNeilBrown clear_bit(R1BIO_BarrierRetry, &r1_bio->state); 1645a9701a30SNeilBrown clear_bit(R1BIO_Barrier, &r1_bio->state); 1646a9701a30SNeilBrown for (i=0; i < conf->raid_disks; i++) 16472f889129SNeilBrown if (r1_bio->bios[i]) 16482f889129SNeilBrown atomic_inc(&r1_bio->remaining); 16492f889129SNeilBrown for (i=0; i < conf->raid_disks; i++) 1650a9701a30SNeilBrown if (r1_bio->bios[i]) { 1651a9701a30SNeilBrown struct bio_vec *bvec; 1652a9701a30SNeilBrown int j; 1653a9701a30SNeilBrown 1654a9701a30SNeilBrown bio = bio_clone(r1_bio->master_bio, GFP_NOIO); 1655a9701a30SNeilBrown /* copy pages from the failed bio, as 1656a9701a30SNeilBrown * this might be a write-behind device */ 1657a9701a30SNeilBrown __bio_for_each_segment(bvec, bio, j, 0) 1658a9701a30SNeilBrown bvec->bv_page = bio_iovec_idx(r1_bio->bios[i], j)->bv_page; 1659a9701a30SNeilBrown bio_put(r1_bio->bios[i]); 1660a9701a30SNeilBrown bio->bi_sector = r1_bio->sector + 1661a9701a30SNeilBrown conf->mirrors[i].rdev->data_offset; 1662a9701a30SNeilBrown bio->bi_bdev = conf->mirrors[i].rdev->bdev; 1663a9701a30SNeilBrown bio->bi_end_io = raid1_end_write_request; 16641ef04fefSDmitry Monakhov bio->bi_rw = WRITE | 16651ef04fefSDmitry Monakhov (do_sync << BIO_RW_SYNCIO); 1666a9701a30SNeilBrown bio->bi_private = r1_bio; 1667a9701a30SNeilBrown r1_bio->bios[i] = bio; 1668a9701a30SNeilBrown generic_make_request(bio); 1669a9701a30SNeilBrown } 16701da177e4SLinus Torvalds } else { 16711da177e4SLinus Torvalds int disk; 1672ddaf22abSNeilBrown 1673ddaf22abSNeilBrown /* we got a read error. Maybe the drive is bad. Maybe just 1674ddaf22abSNeilBrown * the block and we can fix it. 1675ddaf22abSNeilBrown * We freeze all other IO, and try reading the block from 1676ddaf22abSNeilBrown * other devices. When we find one, we re-write 1677ddaf22abSNeilBrown * and check it that fixes the read error. 1678ddaf22abSNeilBrown * This is all done synchronously while the array is 1679ddaf22abSNeilBrown * frozen 1680ddaf22abSNeilBrown */ 1681867868fbSNeilBrown if (mddev->ro == 0) { 1682ddaf22abSNeilBrown freeze_array(conf); 1683867868fbSNeilBrown fix_read_error(conf, r1_bio->read_disk, 1684867868fbSNeilBrown r1_bio->sector, 1685867868fbSNeilBrown r1_bio->sectors); 1686ddaf22abSNeilBrown unfreeze_array(conf); 1687d0e26078SNeilBrown } else 1688d0e26078SNeilBrown md_error(mddev, 1689d0e26078SNeilBrown conf->mirrors[r1_bio->read_disk].rdev); 1690ddaf22abSNeilBrown 16911da177e4SLinus Torvalds bio = r1_bio->bios[r1_bio->read_disk]; 1692d0e26078SNeilBrown if ((disk=read_balance(conf, r1_bio)) == -1) { 16939dd1e2faSNeilBrown printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O" 16941da177e4SLinus Torvalds " read error for block %llu\n", 16959dd1e2faSNeilBrown mdname(mddev), 16961da177e4SLinus Torvalds bdevname(bio->bi_bdev,b), 16971da177e4SLinus Torvalds (unsigned long long)r1_bio->sector); 16981da177e4SLinus Torvalds raid_end_bio_io(r1_bio); 16991da177e4SLinus Torvalds } else { 17001f98a13fSJens Axboe const bool do_sync = bio_rw_flagged(r1_bio->master_bio, BIO_RW_SYNCIO); 1701cf30a473SNeilBrown r1_bio->bios[r1_bio->read_disk] = 1702cf30a473SNeilBrown mddev->ro ? IO_BLOCKED : NULL; 17031da177e4SLinus Torvalds r1_bio->read_disk = disk; 17041da177e4SLinus Torvalds bio_put(bio); 17051da177e4SLinus Torvalds bio = bio_clone(r1_bio->master_bio, GFP_NOIO); 17061da177e4SLinus Torvalds r1_bio->bios[r1_bio->read_disk] = bio; 17071da177e4SLinus Torvalds rdev = conf->mirrors[disk].rdev; 17081da177e4SLinus Torvalds if (printk_ratelimit()) 17099dd1e2faSNeilBrown printk(KERN_ERR "md/raid1:%s: redirecting sector %llu to" 1710d754c5aeSNeilBrown " other mirror: %s\n", 17119dd1e2faSNeilBrown mdname(mddev), 1712d754c5aeSNeilBrown (unsigned long long)r1_bio->sector, 1713d754c5aeSNeilBrown bdevname(rdev->bdev,b)); 17141da177e4SLinus Torvalds bio->bi_sector = r1_bio->sector + rdev->data_offset; 17151da177e4SLinus Torvalds bio->bi_bdev = rdev->bdev; 17161da177e4SLinus Torvalds bio->bi_end_io = raid1_end_read_request; 17171ef04fefSDmitry Monakhov bio->bi_rw = READ | (do_sync << BIO_RW_SYNCIO); 17181da177e4SLinus Torvalds bio->bi_private = r1_bio; 17191da177e4SLinus Torvalds unplug = 1; 17201da177e4SLinus Torvalds generic_make_request(bio); 17211da177e4SLinus Torvalds } 17221da177e4SLinus Torvalds } 17231d9d5241SNeilBrown cond_resched(); 17241da177e4SLinus Torvalds } 17251da177e4SLinus Torvalds if (unplug) 17261da177e4SLinus Torvalds unplug_slaves(mddev); 17271da177e4SLinus Torvalds } 17281da177e4SLinus Torvalds 17291da177e4SLinus Torvalds 17301da177e4SLinus Torvalds static int init_resync(conf_t *conf) 17311da177e4SLinus Torvalds { 17321da177e4SLinus Torvalds int buffs; 17331da177e4SLinus Torvalds 17341da177e4SLinus Torvalds buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE; 17359e77c485SEric Sesterhenn BUG_ON(conf->r1buf_pool); 17361da177e4SLinus Torvalds conf->r1buf_pool = mempool_create(buffs, r1buf_pool_alloc, r1buf_pool_free, 17371da177e4SLinus Torvalds conf->poolinfo); 17381da177e4SLinus Torvalds if (!conf->r1buf_pool) 17391da177e4SLinus Torvalds return -ENOMEM; 17401da177e4SLinus Torvalds conf->next_resync = 0; 17411da177e4SLinus Torvalds return 0; 17421da177e4SLinus Torvalds } 17431da177e4SLinus Torvalds 17441da177e4SLinus Torvalds /* 17451da177e4SLinus Torvalds * perform a "sync" on one "block" 17461da177e4SLinus Torvalds * 17471da177e4SLinus Torvalds * We need to make sure that no normal I/O request - particularly write 17481da177e4SLinus Torvalds * requests - conflict with active sync requests. 17491da177e4SLinus Torvalds * 17501da177e4SLinus Torvalds * This is achieved by tracking pending requests and a 'barrier' concept 17511da177e4SLinus Torvalds * that can be installed to exclude normal IO requests. 17521da177e4SLinus Torvalds */ 17531da177e4SLinus Torvalds 175457afd89fSNeilBrown static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster) 17551da177e4SLinus Torvalds { 1756070ec55dSNeilBrown conf_t *conf = mddev->private; 17571da177e4SLinus Torvalds r1bio_t *r1_bio; 17581da177e4SLinus Torvalds struct bio *bio; 17591da177e4SLinus Torvalds sector_t max_sector, nr_sectors; 17603e198f78SNeilBrown int disk = -1; 17611da177e4SLinus Torvalds int i; 17623e198f78SNeilBrown int wonly = -1; 17633e198f78SNeilBrown int write_targets = 0, read_targets = 0; 1764191ea9b2SNeilBrown int sync_blocks; 1765e3b9703eSNeilBrown int still_degraded = 0; 17661da177e4SLinus Torvalds 17671da177e4SLinus Torvalds if (!conf->r1buf_pool) 17681da177e4SLinus Torvalds if (init_resync(conf)) 176957afd89fSNeilBrown return 0; 17701da177e4SLinus Torvalds 177158c0fed4SAndre Noll max_sector = mddev->dev_sectors; 17721da177e4SLinus Torvalds if (sector_nr >= max_sector) { 1773191ea9b2SNeilBrown /* If we aborted, we need to abort the 1774191ea9b2SNeilBrown * sync on the 'current' bitmap chunk (there will 1775191ea9b2SNeilBrown * only be one in raid1 resync. 1776191ea9b2SNeilBrown * We can find the current addess in mddev->curr_resync 1777191ea9b2SNeilBrown */ 17786a806c51SNeilBrown if (mddev->curr_resync < max_sector) /* aborted */ 17796a806c51SNeilBrown bitmap_end_sync(mddev->bitmap, mddev->curr_resync, 1780191ea9b2SNeilBrown &sync_blocks, 1); 17816a806c51SNeilBrown else /* completed sync */ 1782191ea9b2SNeilBrown conf->fullsync = 0; 17836a806c51SNeilBrown 17846a806c51SNeilBrown bitmap_close_sync(mddev->bitmap); 17851da177e4SLinus Torvalds close_sync(conf); 17861da177e4SLinus Torvalds return 0; 17871da177e4SLinus Torvalds } 17881da177e4SLinus Torvalds 178907d84d10SNeilBrown if (mddev->bitmap == NULL && 179007d84d10SNeilBrown mddev->recovery_cp == MaxSector && 17916394cca5SNeilBrown !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && 179207d84d10SNeilBrown conf->fullsync == 0) { 179307d84d10SNeilBrown *skipped = 1; 179407d84d10SNeilBrown return max_sector - sector_nr; 179507d84d10SNeilBrown } 17966394cca5SNeilBrown /* before building a request, check if we can skip these blocks.. 17976394cca5SNeilBrown * This call the bitmap_start_sync doesn't actually record anything 17986394cca5SNeilBrown */ 1799e3b9703eSNeilBrown if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && 1800e5de485fSNeilBrown !conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { 1801191ea9b2SNeilBrown /* We can skip this block, and probably several more */ 1802191ea9b2SNeilBrown *skipped = 1; 1803191ea9b2SNeilBrown return sync_blocks; 1804191ea9b2SNeilBrown } 18051da177e4SLinus Torvalds /* 180617999be4SNeilBrown * If there is non-resync activity waiting for a turn, 180717999be4SNeilBrown * and resync is going fast enough, 180817999be4SNeilBrown * then let it though before starting on this new sync request. 18091da177e4SLinus Torvalds */ 181017999be4SNeilBrown if (!go_faster && conf->nr_waiting) 18111da177e4SLinus Torvalds msleep_interruptible(1000); 181217999be4SNeilBrown 1813b47490c9SNeilBrown bitmap_cond_end_sync(mddev->bitmap, sector_nr); 181417999be4SNeilBrown raise_barrier(conf); 181517999be4SNeilBrown 181617999be4SNeilBrown conf->next_resync = sector_nr; 18171da177e4SLinus Torvalds 18181da177e4SLinus Torvalds r1_bio = mempool_alloc(conf->r1buf_pool, GFP_NOIO); 18193e198f78SNeilBrown rcu_read_lock(); 18203e198f78SNeilBrown /* 18213e198f78SNeilBrown * If we get a correctably read error during resync or recovery, 18223e198f78SNeilBrown * we might want to read from a different device. So we 18233e198f78SNeilBrown * flag all drives that could conceivably be read from for READ, 18243e198f78SNeilBrown * and any others (which will be non-In_sync devices) for WRITE. 18253e198f78SNeilBrown * If a read fails, we try reading from something else for which READ 18263e198f78SNeilBrown * is OK. 18273e198f78SNeilBrown */ 18281da177e4SLinus Torvalds 18291da177e4SLinus Torvalds r1_bio->mddev = mddev; 18301da177e4SLinus Torvalds r1_bio->sector = sector_nr; 1831191ea9b2SNeilBrown r1_bio->state = 0; 18321da177e4SLinus Torvalds set_bit(R1BIO_IsSync, &r1_bio->state); 18331da177e4SLinus Torvalds 18341da177e4SLinus Torvalds for (i=0; i < conf->raid_disks; i++) { 18353e198f78SNeilBrown mdk_rdev_t *rdev; 18361da177e4SLinus Torvalds bio = r1_bio->bios[i]; 18371da177e4SLinus Torvalds 18381da177e4SLinus Torvalds /* take from bio_init */ 18391da177e4SLinus Torvalds bio->bi_next = NULL; 18401da177e4SLinus Torvalds bio->bi_flags |= 1 << BIO_UPTODATE; 1841802ba064SNeilBrown bio->bi_rw = READ; 18421da177e4SLinus Torvalds bio->bi_vcnt = 0; 18431da177e4SLinus Torvalds bio->bi_idx = 0; 18441da177e4SLinus Torvalds bio->bi_phys_segments = 0; 18451da177e4SLinus Torvalds bio->bi_size = 0; 18461da177e4SLinus Torvalds bio->bi_end_io = NULL; 18471da177e4SLinus Torvalds bio->bi_private = NULL; 18481da177e4SLinus Torvalds 18493e198f78SNeilBrown rdev = rcu_dereference(conf->mirrors[i].rdev); 18503e198f78SNeilBrown if (rdev == NULL || 18513e198f78SNeilBrown test_bit(Faulty, &rdev->flags)) { 1852e3b9703eSNeilBrown still_degraded = 1; 1853e3b9703eSNeilBrown continue; 18543e198f78SNeilBrown } else if (!test_bit(In_sync, &rdev->flags)) { 18551da177e4SLinus Torvalds bio->bi_rw = WRITE; 18561da177e4SLinus Torvalds bio->bi_end_io = end_sync_write; 18571da177e4SLinus Torvalds write_targets ++; 18583e198f78SNeilBrown } else { 18593e198f78SNeilBrown /* may need to read from here */ 18603e198f78SNeilBrown bio->bi_rw = READ; 18613e198f78SNeilBrown bio->bi_end_io = end_sync_read; 18623e198f78SNeilBrown if (test_bit(WriteMostly, &rdev->flags)) { 18633e198f78SNeilBrown if (wonly < 0) 18643e198f78SNeilBrown wonly = i; 18653e198f78SNeilBrown } else { 18663e198f78SNeilBrown if (disk < 0) 18673e198f78SNeilBrown disk = i; 18683e198f78SNeilBrown } 18693e198f78SNeilBrown read_targets++; 18703e198f78SNeilBrown } 18713e198f78SNeilBrown atomic_inc(&rdev->nr_pending); 18723e198f78SNeilBrown bio->bi_sector = sector_nr + rdev->data_offset; 18733e198f78SNeilBrown bio->bi_bdev = rdev->bdev; 18741da177e4SLinus Torvalds bio->bi_private = r1_bio; 18751da177e4SLinus Torvalds } 18763e198f78SNeilBrown rcu_read_unlock(); 18773e198f78SNeilBrown if (disk < 0) 18783e198f78SNeilBrown disk = wonly; 18793e198f78SNeilBrown r1_bio->read_disk = disk; 1880191ea9b2SNeilBrown 18813e198f78SNeilBrown if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0) 18823e198f78SNeilBrown /* extra read targets are also write targets */ 18833e198f78SNeilBrown write_targets += read_targets-1; 18843e198f78SNeilBrown 18853e198f78SNeilBrown if (write_targets == 0 || read_targets == 0) { 18861da177e4SLinus Torvalds /* There is nowhere to write, so all non-sync 18871da177e4SLinus Torvalds * drives must be failed - so we are finished 18881da177e4SLinus Torvalds */ 188957afd89fSNeilBrown sector_t rv = max_sector - sector_nr; 189057afd89fSNeilBrown *skipped = 1; 18911da177e4SLinus Torvalds put_buf(r1_bio); 18921da177e4SLinus Torvalds return rv; 18931da177e4SLinus Torvalds } 18941da177e4SLinus Torvalds 1895c6207277SNeilBrown if (max_sector > mddev->resync_max) 1896c6207277SNeilBrown max_sector = mddev->resync_max; /* Don't do IO beyond here */ 18971da177e4SLinus Torvalds nr_sectors = 0; 1898289e99e8SNeilBrown sync_blocks = 0; 18991da177e4SLinus Torvalds do { 19001da177e4SLinus Torvalds struct page *page; 19011da177e4SLinus Torvalds int len = PAGE_SIZE; 19021da177e4SLinus Torvalds if (sector_nr + (len>>9) > max_sector) 19031da177e4SLinus Torvalds len = (max_sector - sector_nr) << 9; 19041da177e4SLinus Torvalds if (len == 0) 19051da177e4SLinus Torvalds break; 1906ab7a30c7SNeilBrown if (sync_blocks == 0) { 19076a806c51SNeilBrown if (!bitmap_start_sync(mddev->bitmap, sector_nr, 1908e3b9703eSNeilBrown &sync_blocks, still_degraded) && 1909e5de485fSNeilBrown !conf->fullsync && 1910e5de485fSNeilBrown !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) 1911191ea9b2SNeilBrown break; 19129e77c485SEric Sesterhenn BUG_ON(sync_blocks < (PAGE_SIZE>>9)); 19136a806c51SNeilBrown if (len > (sync_blocks<<9)) 19146a806c51SNeilBrown len = sync_blocks<<9; 1915ab7a30c7SNeilBrown } 1916191ea9b2SNeilBrown 19171da177e4SLinus Torvalds for (i=0 ; i < conf->raid_disks; i++) { 19181da177e4SLinus Torvalds bio = r1_bio->bios[i]; 19191da177e4SLinus Torvalds if (bio->bi_end_io) { 1920d11c171eSNeilBrown page = bio->bi_io_vec[bio->bi_vcnt].bv_page; 19211da177e4SLinus Torvalds if (bio_add_page(bio, page, len, 0) == 0) { 19221da177e4SLinus Torvalds /* stop here */ 1923d11c171eSNeilBrown bio->bi_io_vec[bio->bi_vcnt].bv_page = page; 19241da177e4SLinus Torvalds while (i > 0) { 19251da177e4SLinus Torvalds i--; 19261da177e4SLinus Torvalds bio = r1_bio->bios[i]; 19276a806c51SNeilBrown if (bio->bi_end_io==NULL) 19286a806c51SNeilBrown continue; 19291da177e4SLinus Torvalds /* remove last page from this bio */ 19301da177e4SLinus Torvalds bio->bi_vcnt--; 19311da177e4SLinus Torvalds bio->bi_size -= len; 19321da177e4SLinus Torvalds bio->bi_flags &= ~(1<< BIO_SEG_VALID); 19331da177e4SLinus Torvalds } 19341da177e4SLinus Torvalds goto bio_full; 19351da177e4SLinus Torvalds } 19361da177e4SLinus Torvalds } 19371da177e4SLinus Torvalds } 19381da177e4SLinus Torvalds nr_sectors += len>>9; 19391da177e4SLinus Torvalds sector_nr += len>>9; 1940191ea9b2SNeilBrown sync_blocks -= (len>>9); 19411da177e4SLinus Torvalds } while (r1_bio->bios[disk]->bi_vcnt < RESYNC_PAGES); 19421da177e4SLinus Torvalds bio_full: 19431da177e4SLinus Torvalds r1_bio->sectors = nr_sectors; 19441da177e4SLinus Torvalds 1945d11c171eSNeilBrown /* For a user-requested sync, we read all readable devices and do a 1946d11c171eSNeilBrown * compare 1947d11c171eSNeilBrown */ 1948d11c171eSNeilBrown if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { 1949d11c171eSNeilBrown atomic_set(&r1_bio->remaining, read_targets); 1950d11c171eSNeilBrown for (i=0; i<conf->raid_disks; i++) { 1951d11c171eSNeilBrown bio = r1_bio->bios[i]; 1952d11c171eSNeilBrown if (bio->bi_end_io == end_sync_read) { 1953ddac7c7eSNeilBrown md_sync_acct(bio->bi_bdev, nr_sectors); 19541da177e4SLinus Torvalds generic_make_request(bio); 1955d11c171eSNeilBrown } 1956d11c171eSNeilBrown } 1957d11c171eSNeilBrown } else { 1958d11c171eSNeilBrown atomic_set(&r1_bio->remaining, 1); 1959d11c171eSNeilBrown bio = r1_bio->bios[r1_bio->read_disk]; 1960ddac7c7eSNeilBrown md_sync_acct(bio->bi_bdev, nr_sectors); 1961d11c171eSNeilBrown generic_make_request(bio); 1962d11c171eSNeilBrown 1963d11c171eSNeilBrown } 19641da177e4SLinus Torvalds return nr_sectors; 19651da177e4SLinus Torvalds } 19661da177e4SLinus Torvalds 196780c3a6ceSDan Williams static sector_t raid1_size(mddev_t *mddev, sector_t sectors, int raid_disks) 196880c3a6ceSDan Williams { 196980c3a6ceSDan Williams if (sectors) 197080c3a6ceSDan Williams return sectors; 197180c3a6ceSDan Williams 197280c3a6ceSDan Williams return mddev->dev_sectors; 197380c3a6ceSDan Williams } 197480c3a6ceSDan Williams 1975709ae487SNeilBrown static conf_t *setup_conf(mddev_t *mddev) 19761da177e4SLinus Torvalds { 19771da177e4SLinus Torvalds conf_t *conf; 1978709ae487SNeilBrown int i; 19791da177e4SLinus Torvalds mirror_info_t *disk; 19801da177e4SLinus Torvalds mdk_rdev_t *rdev; 1981709ae487SNeilBrown int err = -ENOMEM; 19821da177e4SLinus Torvalds 19839ffae0cfSNeilBrown conf = kzalloc(sizeof(conf_t), GFP_KERNEL); 19841da177e4SLinus Torvalds if (!conf) 1985709ae487SNeilBrown goto abort; 19861da177e4SLinus Torvalds 19879ffae0cfSNeilBrown conf->mirrors = kzalloc(sizeof(struct mirror_info)*mddev->raid_disks, 19881da177e4SLinus Torvalds GFP_KERNEL); 19891da177e4SLinus Torvalds if (!conf->mirrors) 1990709ae487SNeilBrown goto abort; 19911da177e4SLinus Torvalds 1992ddaf22abSNeilBrown conf->tmppage = alloc_page(GFP_KERNEL); 1993ddaf22abSNeilBrown if (!conf->tmppage) 1994709ae487SNeilBrown goto abort; 1995ddaf22abSNeilBrown 1996709ae487SNeilBrown conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL); 19971da177e4SLinus Torvalds if (!conf->poolinfo) 1998709ae487SNeilBrown goto abort; 19991da177e4SLinus Torvalds conf->poolinfo->raid_disks = mddev->raid_disks; 20001da177e4SLinus Torvalds conf->r1bio_pool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc, 20011da177e4SLinus Torvalds r1bio_pool_free, 20021da177e4SLinus Torvalds conf->poolinfo); 20031da177e4SLinus Torvalds if (!conf->r1bio_pool) 2004709ae487SNeilBrown goto abort; 2005709ae487SNeilBrown 2006ed9bfdf1SNeilBrown conf->poolinfo->mddev = mddev; 20071da177e4SLinus Torvalds 2008e7e72bf6SNeil Brown spin_lock_init(&conf->device_lock); 2009159ec1fcSCheng Renquan list_for_each_entry(rdev, &mddev->disks, same_set) { 2010709ae487SNeilBrown int disk_idx = rdev->raid_disk; 20111da177e4SLinus Torvalds if (disk_idx >= mddev->raid_disks 20121da177e4SLinus Torvalds || disk_idx < 0) 20131da177e4SLinus Torvalds continue; 20141da177e4SLinus Torvalds disk = conf->mirrors + disk_idx; 20151da177e4SLinus Torvalds 20161da177e4SLinus Torvalds disk->rdev = rdev; 20171da177e4SLinus Torvalds 20181da177e4SLinus Torvalds disk->head_position = 0; 20191da177e4SLinus Torvalds } 20201da177e4SLinus Torvalds conf->raid_disks = mddev->raid_disks; 20211da177e4SLinus Torvalds conf->mddev = mddev; 20221da177e4SLinus Torvalds INIT_LIST_HEAD(&conf->retry_list); 20231da177e4SLinus Torvalds 20241da177e4SLinus Torvalds spin_lock_init(&conf->resync_lock); 202517999be4SNeilBrown init_waitqueue_head(&conf->wait_barrier); 20261da177e4SLinus Torvalds 2027191ea9b2SNeilBrown bio_list_init(&conf->pending_bio_list); 2028191ea9b2SNeilBrown bio_list_init(&conf->flushing_bio_list); 2029191ea9b2SNeilBrown 2030709ae487SNeilBrown conf->last_used = -1; 20311da177e4SLinus Torvalds for (i = 0; i < conf->raid_disks; i++) { 20321da177e4SLinus Torvalds 20331da177e4SLinus Torvalds disk = conf->mirrors + i; 20341da177e4SLinus Torvalds 20355fd6c1dcSNeilBrown if (!disk->rdev || 20365fd6c1dcSNeilBrown !test_bit(In_sync, &disk->rdev->flags)) { 20371da177e4SLinus Torvalds disk->head_position = 0; 2038918f0238SNeilBrown if (disk->rdev) 203917571284SNeilBrown conf->fullsync = 1; 2040709ae487SNeilBrown } else if (conf->last_used < 0) 2041709ae487SNeilBrown /* 2042709ae487SNeilBrown * The first working device is used as a 2043709ae487SNeilBrown * starting point to read balancing. 2044709ae487SNeilBrown */ 2045709ae487SNeilBrown conf->last_used = i; 20461da177e4SLinus Torvalds } 2047709ae487SNeilBrown 2048709ae487SNeilBrown err = -EIO; 2049709ae487SNeilBrown if (conf->last_used < 0) { 20509dd1e2faSNeilBrown printk(KERN_ERR "md/raid1:%s: no operational mirrors\n", 205111ce99e6SNeilBrown mdname(mddev)); 2052709ae487SNeilBrown goto abort; 205311ce99e6SNeilBrown } 2054709ae487SNeilBrown err = -ENOMEM; 2055709ae487SNeilBrown conf->thread = md_register_thread(raid1d, mddev, NULL); 2056709ae487SNeilBrown if (!conf->thread) { 20571da177e4SLinus Torvalds printk(KERN_ERR 20589dd1e2faSNeilBrown "md/raid1:%s: couldn't allocate thread\n", 20591da177e4SLinus Torvalds mdname(mddev)); 2060709ae487SNeilBrown goto abort; 20611da177e4SLinus Torvalds } 2062191ea9b2SNeilBrown 2063709ae487SNeilBrown return conf; 2064709ae487SNeilBrown 2065709ae487SNeilBrown abort: 2066709ae487SNeilBrown if (conf) { 2067709ae487SNeilBrown if (conf->r1bio_pool) 2068709ae487SNeilBrown mempool_destroy(conf->r1bio_pool); 2069709ae487SNeilBrown kfree(conf->mirrors); 2070709ae487SNeilBrown safe_put_page(conf->tmppage); 2071709ae487SNeilBrown kfree(conf->poolinfo); 2072709ae487SNeilBrown kfree(conf); 2073709ae487SNeilBrown } 2074709ae487SNeilBrown return ERR_PTR(err); 2075709ae487SNeilBrown } 2076709ae487SNeilBrown 2077709ae487SNeilBrown static int run(mddev_t *mddev) 2078709ae487SNeilBrown { 2079709ae487SNeilBrown conf_t *conf; 2080709ae487SNeilBrown int i; 2081709ae487SNeilBrown mdk_rdev_t *rdev; 2082709ae487SNeilBrown 2083709ae487SNeilBrown if (mddev->level != 1) { 20849dd1e2faSNeilBrown printk(KERN_ERR "md/raid1:%s: raid level not set to mirroring (%d)\n", 2085709ae487SNeilBrown mdname(mddev), mddev->level); 2086709ae487SNeilBrown return -EIO; 2087709ae487SNeilBrown } 2088709ae487SNeilBrown if (mddev->reshape_position != MaxSector) { 20899dd1e2faSNeilBrown printk(KERN_ERR "md/raid1:%s: reshape_position set but not supported\n", 2090709ae487SNeilBrown mdname(mddev)); 2091709ae487SNeilBrown return -EIO; 2092709ae487SNeilBrown } 2093709ae487SNeilBrown /* 2094709ae487SNeilBrown * copy the already verified devices into our private RAID1 2095709ae487SNeilBrown * bookkeeping area. [whatever we allocate in run(), 2096709ae487SNeilBrown * should be freed in stop()] 2097709ae487SNeilBrown */ 2098709ae487SNeilBrown if (mddev->private == NULL) 2099709ae487SNeilBrown conf = setup_conf(mddev); 2100709ae487SNeilBrown else 2101709ae487SNeilBrown conf = mddev->private; 2102709ae487SNeilBrown 2103709ae487SNeilBrown if (IS_ERR(conf)) 2104709ae487SNeilBrown return PTR_ERR(conf); 2105709ae487SNeilBrown 2106709ae487SNeilBrown mddev->queue->queue_lock = &conf->device_lock; 2107709ae487SNeilBrown list_for_each_entry(rdev, &mddev->disks, same_set) { 2108709ae487SNeilBrown disk_stack_limits(mddev->gendisk, rdev->bdev, 2109709ae487SNeilBrown rdev->data_offset << 9); 2110709ae487SNeilBrown /* as we don't honour merge_bvec_fn, we must never risk 2111627a2d3cSNeilBrown * violating it, so limit ->max_segments to 1 lying within 2112627a2d3cSNeilBrown * a single page, as a one page request is never in violation. 2113709ae487SNeilBrown */ 2114627a2d3cSNeilBrown if (rdev->bdev->bd_disk->queue->merge_bvec_fn) { 2115627a2d3cSNeilBrown blk_queue_max_segments(mddev->queue, 1); 2116627a2d3cSNeilBrown blk_queue_segment_boundary(mddev->queue, 2117627a2d3cSNeilBrown PAGE_CACHE_SIZE - 1); 2118627a2d3cSNeilBrown } 2119709ae487SNeilBrown } 2120709ae487SNeilBrown 2121709ae487SNeilBrown mddev->degraded = 0; 2122709ae487SNeilBrown for (i=0; i < conf->raid_disks; i++) 2123709ae487SNeilBrown if (conf->mirrors[i].rdev == NULL || 2124709ae487SNeilBrown !test_bit(In_sync, &conf->mirrors[i].rdev->flags) || 2125709ae487SNeilBrown test_bit(Faulty, &conf->mirrors[i].rdev->flags)) 2126709ae487SNeilBrown mddev->degraded++; 2127709ae487SNeilBrown 2128709ae487SNeilBrown if (conf->raid_disks - mddev->degraded == 1) 2129709ae487SNeilBrown mddev->recovery_cp = MaxSector; 2130709ae487SNeilBrown 21318c6ac868SAndre Noll if (mddev->recovery_cp != MaxSector) 21329dd1e2faSNeilBrown printk(KERN_NOTICE "md/raid1:%s: not clean" 21338c6ac868SAndre Noll " -- starting background reconstruction\n", 21348c6ac868SAndre Noll mdname(mddev)); 21351da177e4SLinus Torvalds printk(KERN_INFO 21369dd1e2faSNeilBrown "md/raid1:%s: active with %d out of %d mirrors\n", 21371da177e4SLinus Torvalds mdname(mddev), mddev->raid_disks - mddev->degraded, 21381da177e4SLinus Torvalds mddev->raid_disks); 2139709ae487SNeilBrown 21401da177e4SLinus Torvalds /* 21411da177e4SLinus Torvalds * Ok, everything is just fine now 21421da177e4SLinus Torvalds */ 2143709ae487SNeilBrown mddev->thread = conf->thread; 2144709ae487SNeilBrown conf->thread = NULL; 2145709ae487SNeilBrown mddev->private = conf; 2146709ae487SNeilBrown 21471f403624SDan Williams md_set_array_sectors(mddev, raid1_size(mddev, 0, 0)); 21481da177e4SLinus Torvalds 21497a5febe9SNeilBrown mddev->queue->unplug_fn = raid1_unplug; 21500d129228SNeilBrown mddev->queue->backing_dev_info.congested_fn = raid1_congested; 21510d129228SNeilBrown mddev->queue->backing_dev_info.congested_data = mddev; 2152ac5e7113SAndre Noll md_integrity_register(mddev); 21531da177e4SLinus Torvalds return 0; 21541da177e4SLinus Torvalds } 21551da177e4SLinus Torvalds 21561da177e4SLinus Torvalds static int stop(mddev_t *mddev) 21571da177e4SLinus Torvalds { 2158070ec55dSNeilBrown conf_t *conf = mddev->private; 21594b6d287fSNeilBrown struct bitmap *bitmap = mddev->bitmap; 21604b6d287fSNeilBrown 21614b6d287fSNeilBrown /* wait for behind writes to complete */ 2162e555190dSNeilBrown if (bitmap && atomic_read(&bitmap->behind_writes) > 0) { 21639dd1e2faSNeilBrown printk(KERN_INFO "md/raid1:%s: behind writes in progress - waiting to stop.\n", 21649dd1e2faSNeilBrown mdname(mddev)); 21654b6d287fSNeilBrown /* need to kick something here to make sure I/O goes? */ 2166e555190dSNeilBrown wait_event(bitmap->behind_wait, 2167e555190dSNeilBrown atomic_read(&bitmap->behind_writes) == 0); 21684b6d287fSNeilBrown } 21691da177e4SLinus Torvalds 2170409c57f3SNeilBrown raise_barrier(conf); 2171409c57f3SNeilBrown lower_barrier(conf); 2172409c57f3SNeilBrown 21731da177e4SLinus Torvalds md_unregister_thread(mddev->thread); 21741da177e4SLinus Torvalds mddev->thread = NULL; 21751da177e4SLinus Torvalds blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ 21761da177e4SLinus Torvalds if (conf->r1bio_pool) 21771da177e4SLinus Torvalds mempool_destroy(conf->r1bio_pool); 21781da177e4SLinus Torvalds kfree(conf->mirrors); 21791da177e4SLinus Torvalds kfree(conf->poolinfo); 21801da177e4SLinus Torvalds kfree(conf); 21811da177e4SLinus Torvalds mddev->private = NULL; 21821da177e4SLinus Torvalds return 0; 21831da177e4SLinus Torvalds } 21841da177e4SLinus Torvalds 21851da177e4SLinus Torvalds static int raid1_resize(mddev_t *mddev, sector_t sectors) 21861da177e4SLinus Torvalds { 21871da177e4SLinus Torvalds /* no resync is happening, and there is enough space 21881da177e4SLinus Torvalds * on all devices, so we can resize. 21891da177e4SLinus Torvalds * We need to make sure resync covers any new space. 21901da177e4SLinus Torvalds * If the array is shrinking we should possibly wait until 21911da177e4SLinus Torvalds * any io in the removed space completes, but it hardly seems 21921da177e4SLinus Torvalds * worth it. 21931da177e4SLinus Torvalds */ 21941f403624SDan Williams md_set_array_sectors(mddev, raid1_size(mddev, sectors, 0)); 2195b522adcdSDan Williams if (mddev->array_sectors > raid1_size(mddev, sectors, 0)) 2196b522adcdSDan Williams return -EINVAL; 2197f233ea5cSAndre Noll set_capacity(mddev->gendisk, mddev->array_sectors); 2198449aad3eSNeilBrown revalidate_disk(mddev->gendisk); 2199b522adcdSDan Williams if (sectors > mddev->dev_sectors && 2200f233ea5cSAndre Noll mddev->recovery_cp == MaxSector) { 220158c0fed4SAndre Noll mddev->recovery_cp = mddev->dev_sectors; 22021da177e4SLinus Torvalds set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 22031da177e4SLinus Torvalds } 2204b522adcdSDan Williams mddev->dev_sectors = sectors; 22054b5c7ae8SNeilBrown mddev->resync_max_sectors = sectors; 22061da177e4SLinus Torvalds return 0; 22071da177e4SLinus Torvalds } 22081da177e4SLinus Torvalds 220963c70c4fSNeilBrown static int raid1_reshape(mddev_t *mddev) 22101da177e4SLinus Torvalds { 22111da177e4SLinus Torvalds /* We need to: 22121da177e4SLinus Torvalds * 1/ resize the r1bio_pool 22131da177e4SLinus Torvalds * 2/ resize conf->mirrors 22141da177e4SLinus Torvalds * 22151da177e4SLinus Torvalds * We allocate a new r1bio_pool if we can. 22161da177e4SLinus Torvalds * Then raise a device barrier and wait until all IO stops. 22171da177e4SLinus Torvalds * Then resize conf->mirrors and swap in the new r1bio pool. 22186ea9c07cSNeilBrown * 22196ea9c07cSNeilBrown * At the same time, we "pack" the devices so that all the missing 22206ea9c07cSNeilBrown * devices have the higher raid_disk numbers. 22211da177e4SLinus Torvalds */ 22221da177e4SLinus Torvalds mempool_t *newpool, *oldpool; 22231da177e4SLinus Torvalds struct pool_info *newpoolinfo; 22241da177e4SLinus Torvalds mirror_info_t *newmirrors; 2225070ec55dSNeilBrown conf_t *conf = mddev->private; 222663c70c4fSNeilBrown int cnt, raid_disks; 2227c04be0aaSNeilBrown unsigned long flags; 2228b5470dc5SDan Williams int d, d2, err; 22291da177e4SLinus Torvalds 223063c70c4fSNeilBrown /* Cannot change chunk_size, layout, or level */ 2231664e7c41SAndre Noll if (mddev->chunk_sectors != mddev->new_chunk_sectors || 223263c70c4fSNeilBrown mddev->layout != mddev->new_layout || 223363c70c4fSNeilBrown mddev->level != mddev->new_level) { 2234664e7c41SAndre Noll mddev->new_chunk_sectors = mddev->chunk_sectors; 223563c70c4fSNeilBrown mddev->new_layout = mddev->layout; 223663c70c4fSNeilBrown mddev->new_level = mddev->level; 223763c70c4fSNeilBrown return -EINVAL; 223863c70c4fSNeilBrown } 223963c70c4fSNeilBrown 2240b5470dc5SDan Williams err = md_allow_write(mddev); 2241b5470dc5SDan Williams if (err) 2242b5470dc5SDan Williams return err; 22432a2275d6SNeilBrown 224463c70c4fSNeilBrown raid_disks = mddev->raid_disks + mddev->delta_disks; 224563c70c4fSNeilBrown 22466ea9c07cSNeilBrown if (raid_disks < conf->raid_disks) { 22476ea9c07cSNeilBrown cnt=0; 22486ea9c07cSNeilBrown for (d= 0; d < conf->raid_disks; d++) 22491da177e4SLinus Torvalds if (conf->mirrors[d].rdev) 22506ea9c07cSNeilBrown cnt++; 22516ea9c07cSNeilBrown if (cnt > raid_disks) 22521da177e4SLinus Torvalds return -EBUSY; 22536ea9c07cSNeilBrown } 22541da177e4SLinus Torvalds 22551da177e4SLinus Torvalds newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL); 22561da177e4SLinus Torvalds if (!newpoolinfo) 22571da177e4SLinus Torvalds return -ENOMEM; 22581da177e4SLinus Torvalds newpoolinfo->mddev = mddev; 22591da177e4SLinus Torvalds newpoolinfo->raid_disks = raid_disks; 22601da177e4SLinus Torvalds 22611da177e4SLinus Torvalds newpool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc, 22621da177e4SLinus Torvalds r1bio_pool_free, newpoolinfo); 22631da177e4SLinus Torvalds if (!newpool) { 22641da177e4SLinus Torvalds kfree(newpoolinfo); 22651da177e4SLinus Torvalds return -ENOMEM; 22661da177e4SLinus Torvalds } 22679ffae0cfSNeilBrown newmirrors = kzalloc(sizeof(struct mirror_info) * raid_disks, GFP_KERNEL); 22681da177e4SLinus Torvalds if (!newmirrors) { 22691da177e4SLinus Torvalds kfree(newpoolinfo); 22701da177e4SLinus Torvalds mempool_destroy(newpool); 22711da177e4SLinus Torvalds return -ENOMEM; 22721da177e4SLinus Torvalds } 22731da177e4SLinus Torvalds 227417999be4SNeilBrown raise_barrier(conf); 22751da177e4SLinus Torvalds 22761da177e4SLinus Torvalds /* ok, everything is stopped */ 22771da177e4SLinus Torvalds oldpool = conf->r1bio_pool; 22781da177e4SLinus Torvalds conf->r1bio_pool = newpool; 22796ea9c07cSNeilBrown 2280a88aa786SNeilBrown for (d = d2 = 0; d < conf->raid_disks; d++) { 2281a88aa786SNeilBrown mdk_rdev_t *rdev = conf->mirrors[d].rdev; 2282a88aa786SNeilBrown if (rdev && rdev->raid_disk != d2) { 2283a88aa786SNeilBrown char nm[20]; 2284a88aa786SNeilBrown sprintf(nm, "rd%d", rdev->raid_disk); 2285a88aa786SNeilBrown sysfs_remove_link(&mddev->kobj, nm); 2286a88aa786SNeilBrown rdev->raid_disk = d2; 2287a88aa786SNeilBrown sprintf(nm, "rd%d", rdev->raid_disk); 2288a88aa786SNeilBrown sysfs_remove_link(&mddev->kobj, nm); 2289a88aa786SNeilBrown if (sysfs_create_link(&mddev->kobj, 2290a88aa786SNeilBrown &rdev->kobj, nm)) 2291a88aa786SNeilBrown printk(KERN_WARNING 22929dd1e2faSNeilBrown "md/raid1:%s: cannot register " 22939dd1e2faSNeilBrown "%s\n", 22949dd1e2faSNeilBrown mdname(mddev), nm); 2295a88aa786SNeilBrown } 2296a88aa786SNeilBrown if (rdev) 2297a88aa786SNeilBrown newmirrors[d2++].rdev = rdev; 22986ea9c07cSNeilBrown } 22991da177e4SLinus Torvalds kfree(conf->mirrors); 23001da177e4SLinus Torvalds conf->mirrors = newmirrors; 23011da177e4SLinus Torvalds kfree(conf->poolinfo); 23021da177e4SLinus Torvalds conf->poolinfo = newpoolinfo; 23031da177e4SLinus Torvalds 2304c04be0aaSNeilBrown spin_lock_irqsave(&conf->device_lock, flags); 23051da177e4SLinus Torvalds mddev->degraded += (raid_disks - conf->raid_disks); 2306c04be0aaSNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 23071da177e4SLinus Torvalds conf->raid_disks = mddev->raid_disks = raid_disks; 230863c70c4fSNeilBrown mddev->delta_disks = 0; 23091da177e4SLinus Torvalds 23106ea9c07cSNeilBrown conf->last_used = 0; /* just make sure it is in-range */ 231117999be4SNeilBrown lower_barrier(conf); 23121da177e4SLinus Torvalds 23131da177e4SLinus Torvalds set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 23141da177e4SLinus Torvalds md_wakeup_thread(mddev->thread); 23151da177e4SLinus Torvalds 23161da177e4SLinus Torvalds mempool_destroy(oldpool); 23171da177e4SLinus Torvalds return 0; 23181da177e4SLinus Torvalds } 23191da177e4SLinus Torvalds 2320500af87aSNeilBrown static void raid1_quiesce(mddev_t *mddev, int state) 232136fa3063SNeilBrown { 2322070ec55dSNeilBrown conf_t *conf = mddev->private; 232336fa3063SNeilBrown 232436fa3063SNeilBrown switch(state) { 23256eef4b21SNeilBrown case 2: /* wake for suspend */ 23266eef4b21SNeilBrown wake_up(&conf->wait_barrier); 23276eef4b21SNeilBrown break; 23289e6603daSNeilBrown case 1: 232917999be4SNeilBrown raise_barrier(conf); 233036fa3063SNeilBrown break; 23319e6603daSNeilBrown case 0: 233217999be4SNeilBrown lower_barrier(conf); 233336fa3063SNeilBrown break; 233436fa3063SNeilBrown } 233536fa3063SNeilBrown } 233636fa3063SNeilBrown 2337709ae487SNeilBrown static void *raid1_takeover(mddev_t *mddev) 2338709ae487SNeilBrown { 2339709ae487SNeilBrown /* raid1 can take over: 2340709ae487SNeilBrown * raid5 with 2 devices, any layout or chunk size 2341709ae487SNeilBrown */ 2342709ae487SNeilBrown if (mddev->level == 5 && mddev->raid_disks == 2) { 2343709ae487SNeilBrown conf_t *conf; 2344709ae487SNeilBrown mddev->new_level = 1; 2345709ae487SNeilBrown mddev->new_layout = 0; 2346709ae487SNeilBrown mddev->new_chunk_sectors = 0; 2347709ae487SNeilBrown conf = setup_conf(mddev); 2348709ae487SNeilBrown if (!IS_ERR(conf)) 2349709ae487SNeilBrown conf->barrier = 1; 2350709ae487SNeilBrown return conf; 2351709ae487SNeilBrown } 2352709ae487SNeilBrown return ERR_PTR(-EINVAL); 2353709ae487SNeilBrown } 23541da177e4SLinus Torvalds 23552604b703SNeilBrown static struct mdk_personality raid1_personality = 23561da177e4SLinus Torvalds { 23571da177e4SLinus Torvalds .name = "raid1", 23582604b703SNeilBrown .level = 1, 23591da177e4SLinus Torvalds .owner = THIS_MODULE, 23601da177e4SLinus Torvalds .make_request = make_request, 23611da177e4SLinus Torvalds .run = run, 23621da177e4SLinus Torvalds .stop = stop, 23631da177e4SLinus Torvalds .status = status, 23641da177e4SLinus Torvalds .error_handler = error, 23651da177e4SLinus Torvalds .hot_add_disk = raid1_add_disk, 23661da177e4SLinus Torvalds .hot_remove_disk= raid1_remove_disk, 23671da177e4SLinus Torvalds .spare_active = raid1_spare_active, 23681da177e4SLinus Torvalds .sync_request = sync_request, 23691da177e4SLinus Torvalds .resize = raid1_resize, 237080c3a6ceSDan Williams .size = raid1_size, 237163c70c4fSNeilBrown .check_reshape = raid1_reshape, 237236fa3063SNeilBrown .quiesce = raid1_quiesce, 2373709ae487SNeilBrown .takeover = raid1_takeover, 23741da177e4SLinus Torvalds }; 23751da177e4SLinus Torvalds 23761da177e4SLinus Torvalds static int __init raid_init(void) 23771da177e4SLinus Torvalds { 23782604b703SNeilBrown return register_md_personality(&raid1_personality); 23791da177e4SLinus Torvalds } 23801da177e4SLinus Torvalds 23811da177e4SLinus Torvalds static void raid_exit(void) 23821da177e4SLinus Torvalds { 23832604b703SNeilBrown unregister_md_personality(&raid1_personality); 23841da177e4SLinus Torvalds } 23851da177e4SLinus Torvalds 23861da177e4SLinus Torvalds module_init(raid_init); 23871da177e4SLinus Torvalds module_exit(raid_exit); 23881da177e4SLinus Torvalds MODULE_LICENSE("GPL"); 23890efb9e61SNeilBrown MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD"); 23901da177e4SLinus Torvalds MODULE_ALIAS("md-personality-3"); /* RAID1 */ 2391d9d166c2SNeilBrown MODULE_ALIAS("md-raid1"); 23922604b703SNeilBrown MODULE_ALIAS("md-level-1"); 2393