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 345a0e3ad6STejun Heo #include <linux/slab.h> 3525570727SStephen Rothwell #include <linux/delay.h> 36bff61975SNeilBrown #include <linux/blkdev.h> 37bff61975SNeilBrown #include <linux/seq_file.h> 3843b2e5d8SNeilBrown #include "md.h" 39ef740c37SChristoph Hellwig #include "raid1.h" 40ef740c37SChristoph Hellwig #include "bitmap.h" 41191ea9b2SNeilBrown 42191ea9b2SNeilBrown #define DEBUG 0 43191ea9b2SNeilBrown #if DEBUG 44191ea9b2SNeilBrown #define PRINTK(x...) printk(x) 45191ea9b2SNeilBrown #else 46191ea9b2SNeilBrown #define PRINTK(x...) 47191ea9b2SNeilBrown #endif 481da177e4SLinus Torvalds 491da177e4SLinus Torvalds /* 501da177e4SLinus Torvalds * Number of guaranteed r1bios in case of extreme VM load: 511da177e4SLinus Torvalds */ 521da177e4SLinus Torvalds #define NR_RAID1_BIOS 256 531da177e4SLinus Torvalds 541da177e4SLinus Torvalds 551da177e4SLinus Torvalds static void unplug_slaves(mddev_t *mddev); 561da177e4SLinus Torvalds 5717999be4SNeilBrown static void allow_barrier(conf_t *conf); 5817999be4SNeilBrown static void lower_barrier(conf_t *conf); 591da177e4SLinus Torvalds 60dd0fc66fSAl Viro static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data) 611da177e4SLinus Torvalds { 621da177e4SLinus Torvalds struct pool_info *pi = data; 631da177e4SLinus Torvalds r1bio_t *r1_bio; 641da177e4SLinus Torvalds int size = offsetof(r1bio_t, bios[pi->raid_disks]); 651da177e4SLinus Torvalds 661da177e4SLinus Torvalds /* allocate a r1bio with room for raid_disks entries in the bios array */ 679ffae0cfSNeilBrown r1_bio = kzalloc(size, gfp_flags); 68ed9bfdf1SNeilBrown if (!r1_bio && pi->mddev) 691da177e4SLinus Torvalds unplug_slaves(pi->mddev); 701da177e4SLinus Torvalds 711da177e4SLinus Torvalds return r1_bio; 721da177e4SLinus Torvalds } 731da177e4SLinus Torvalds 741da177e4SLinus Torvalds static void r1bio_pool_free(void *r1_bio, void *data) 751da177e4SLinus Torvalds { 761da177e4SLinus Torvalds kfree(r1_bio); 771da177e4SLinus Torvalds } 781da177e4SLinus Torvalds 791da177e4SLinus Torvalds #define RESYNC_BLOCK_SIZE (64*1024) 801da177e4SLinus Torvalds //#define RESYNC_BLOCK_SIZE PAGE_SIZE 811da177e4SLinus Torvalds #define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9) 821da177e4SLinus Torvalds #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE) 831da177e4SLinus Torvalds #define RESYNC_WINDOW (2048*1024) 841da177e4SLinus Torvalds 85dd0fc66fSAl Viro static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data) 861da177e4SLinus Torvalds { 871da177e4SLinus Torvalds struct pool_info *pi = data; 881da177e4SLinus Torvalds struct page *page; 891da177e4SLinus Torvalds r1bio_t *r1_bio; 901da177e4SLinus Torvalds struct bio *bio; 911da177e4SLinus Torvalds int i, j; 921da177e4SLinus Torvalds 931da177e4SLinus Torvalds r1_bio = r1bio_pool_alloc(gfp_flags, pi); 941da177e4SLinus Torvalds if (!r1_bio) { 951da177e4SLinus Torvalds unplug_slaves(pi->mddev); 961da177e4SLinus Torvalds return NULL; 971da177e4SLinus Torvalds } 981da177e4SLinus Torvalds 991da177e4SLinus Torvalds /* 1001da177e4SLinus Torvalds * Allocate bios : 1 for reading, n-1 for writing 1011da177e4SLinus Torvalds */ 1021da177e4SLinus Torvalds for (j = pi->raid_disks ; j-- ; ) { 1036746557fSNeilBrown bio = bio_kmalloc(gfp_flags, RESYNC_PAGES); 1041da177e4SLinus Torvalds if (!bio) 1051da177e4SLinus Torvalds goto out_free_bio; 1061da177e4SLinus Torvalds r1_bio->bios[j] = bio; 1071da177e4SLinus Torvalds } 1081da177e4SLinus Torvalds /* 1091da177e4SLinus Torvalds * Allocate RESYNC_PAGES data pages and attach them to 110d11c171eSNeilBrown * the first bio. 111d11c171eSNeilBrown * If this is a user-requested check/repair, allocate 112d11c171eSNeilBrown * RESYNC_PAGES for each bio. 1131da177e4SLinus Torvalds */ 114d11c171eSNeilBrown if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) 115d11c171eSNeilBrown j = pi->raid_disks; 116d11c171eSNeilBrown else 117d11c171eSNeilBrown j = 1; 118d11c171eSNeilBrown while(j--) { 119d11c171eSNeilBrown bio = r1_bio->bios[j]; 1201da177e4SLinus Torvalds for (i = 0; i < RESYNC_PAGES; i++) { 1211da177e4SLinus Torvalds page = alloc_page(gfp_flags); 1221da177e4SLinus Torvalds if (unlikely(!page)) 1231da177e4SLinus Torvalds goto out_free_pages; 1241da177e4SLinus Torvalds 1251da177e4SLinus Torvalds bio->bi_io_vec[i].bv_page = page; 126303a0e11SNeilBrown bio->bi_vcnt = i+1; 1271da177e4SLinus Torvalds } 128d11c171eSNeilBrown } 129d11c171eSNeilBrown /* If not user-requests, copy the page pointers to all bios */ 130d11c171eSNeilBrown if (!test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) { 131d11c171eSNeilBrown for (i=0; i<RESYNC_PAGES ; i++) 132d11c171eSNeilBrown for (j=1; j<pi->raid_disks; j++) 133d11c171eSNeilBrown r1_bio->bios[j]->bi_io_vec[i].bv_page = 134d11c171eSNeilBrown r1_bio->bios[0]->bi_io_vec[i].bv_page; 135d11c171eSNeilBrown } 1361da177e4SLinus Torvalds 1371da177e4SLinus Torvalds r1_bio->master_bio = NULL; 1381da177e4SLinus Torvalds 1391da177e4SLinus Torvalds return r1_bio; 1401da177e4SLinus Torvalds 1411da177e4SLinus Torvalds out_free_pages: 142d11c171eSNeilBrown for (j=0 ; j < pi->raid_disks; j++) 143303a0e11SNeilBrown for (i=0; i < r1_bio->bios[j]->bi_vcnt ; i++) 144303a0e11SNeilBrown put_page(r1_bio->bios[j]->bi_io_vec[i].bv_page); 145d11c171eSNeilBrown j = -1; 1461da177e4SLinus Torvalds out_free_bio: 1471da177e4SLinus Torvalds while ( ++j < pi->raid_disks ) 1481da177e4SLinus Torvalds bio_put(r1_bio->bios[j]); 1491da177e4SLinus Torvalds r1bio_pool_free(r1_bio, data); 1501da177e4SLinus Torvalds return NULL; 1511da177e4SLinus Torvalds } 1521da177e4SLinus Torvalds 1531da177e4SLinus Torvalds static void r1buf_pool_free(void *__r1_bio, void *data) 1541da177e4SLinus Torvalds { 1551da177e4SLinus Torvalds struct pool_info *pi = data; 156d11c171eSNeilBrown int i,j; 1571da177e4SLinus Torvalds r1bio_t *r1bio = __r1_bio; 1581da177e4SLinus Torvalds 159d11c171eSNeilBrown for (i = 0; i < RESYNC_PAGES; i++) 160d11c171eSNeilBrown for (j = pi->raid_disks; j-- ;) { 161d11c171eSNeilBrown if (j == 0 || 162d11c171eSNeilBrown r1bio->bios[j]->bi_io_vec[i].bv_page != 163d11c171eSNeilBrown r1bio->bios[0]->bi_io_vec[i].bv_page) 1641345b1d8SNeilBrown safe_put_page(r1bio->bios[j]->bi_io_vec[i].bv_page); 1651da177e4SLinus Torvalds } 1661da177e4SLinus Torvalds for (i=0 ; i < pi->raid_disks; i++) 1671da177e4SLinus Torvalds bio_put(r1bio->bios[i]); 1681da177e4SLinus Torvalds 1691da177e4SLinus Torvalds r1bio_pool_free(r1bio, data); 1701da177e4SLinus Torvalds } 1711da177e4SLinus Torvalds 1721da177e4SLinus Torvalds static void put_all_bios(conf_t *conf, r1bio_t *r1_bio) 1731da177e4SLinus Torvalds { 1741da177e4SLinus Torvalds int i; 1751da177e4SLinus Torvalds 1761da177e4SLinus Torvalds for (i = 0; i < conf->raid_disks; i++) { 1771da177e4SLinus Torvalds struct bio **bio = r1_bio->bios + i; 178cf30a473SNeilBrown if (*bio && *bio != IO_BLOCKED) 1791da177e4SLinus Torvalds bio_put(*bio); 1801da177e4SLinus Torvalds *bio = NULL; 1811da177e4SLinus Torvalds } 1821da177e4SLinus Torvalds } 1831da177e4SLinus Torvalds 184858119e1SArjan van de Ven static void free_r1bio(r1bio_t *r1_bio) 1851da177e4SLinus Torvalds { 186070ec55dSNeilBrown conf_t *conf = r1_bio->mddev->private; 1871da177e4SLinus Torvalds 1881da177e4SLinus Torvalds /* 1891da177e4SLinus Torvalds * Wake up any possible resync thread that waits for the device 1901da177e4SLinus Torvalds * to go idle. 1911da177e4SLinus Torvalds */ 19217999be4SNeilBrown allow_barrier(conf); 1931da177e4SLinus Torvalds 1941da177e4SLinus Torvalds put_all_bios(conf, r1_bio); 1951da177e4SLinus Torvalds mempool_free(r1_bio, conf->r1bio_pool); 1961da177e4SLinus Torvalds } 1971da177e4SLinus Torvalds 198858119e1SArjan van de Ven static void put_buf(r1bio_t *r1_bio) 1991da177e4SLinus Torvalds { 200070ec55dSNeilBrown conf_t *conf = r1_bio->mddev->private; 2013e198f78SNeilBrown int i; 2023e198f78SNeilBrown 2033e198f78SNeilBrown for (i=0; i<conf->raid_disks; i++) { 2043e198f78SNeilBrown struct bio *bio = r1_bio->bios[i]; 2053e198f78SNeilBrown if (bio->bi_end_io) 2063e198f78SNeilBrown rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev); 2073e198f78SNeilBrown } 2081da177e4SLinus Torvalds 2091da177e4SLinus Torvalds mempool_free(r1_bio, conf->r1buf_pool); 2101da177e4SLinus Torvalds 21117999be4SNeilBrown lower_barrier(conf); 2121da177e4SLinus Torvalds } 2131da177e4SLinus Torvalds 2141da177e4SLinus Torvalds static void reschedule_retry(r1bio_t *r1_bio) 2151da177e4SLinus Torvalds { 2161da177e4SLinus Torvalds unsigned long flags; 2171da177e4SLinus Torvalds mddev_t *mddev = r1_bio->mddev; 218070ec55dSNeilBrown conf_t *conf = mddev->private; 2191da177e4SLinus Torvalds 2201da177e4SLinus Torvalds spin_lock_irqsave(&conf->device_lock, flags); 2211da177e4SLinus Torvalds list_add(&r1_bio->retry_list, &conf->retry_list); 222ddaf22abSNeilBrown conf->nr_queued ++; 2231da177e4SLinus Torvalds spin_unlock_irqrestore(&conf->device_lock, flags); 2241da177e4SLinus Torvalds 22517999be4SNeilBrown wake_up(&conf->wait_barrier); 2261da177e4SLinus Torvalds md_wakeup_thread(mddev->thread); 2271da177e4SLinus Torvalds } 2281da177e4SLinus Torvalds 2291da177e4SLinus Torvalds /* 2301da177e4SLinus Torvalds * raid_end_bio_io() is called when we have finished servicing a mirrored 2311da177e4SLinus Torvalds * operation and are ready to return a success/failure code to the buffer 2321da177e4SLinus Torvalds * cache layer. 2331da177e4SLinus Torvalds */ 2341da177e4SLinus Torvalds static void raid_end_bio_io(r1bio_t *r1_bio) 2351da177e4SLinus Torvalds { 2361da177e4SLinus Torvalds struct bio *bio = r1_bio->master_bio; 2371da177e4SLinus Torvalds 2384b6d287fSNeilBrown /* if nobody has done the final endio yet, do it now */ 2394b6d287fSNeilBrown if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) { 2404b6d287fSNeilBrown PRINTK(KERN_DEBUG "raid1: sync end %s on sectors %llu-%llu\n", 2414b6d287fSNeilBrown (bio_data_dir(bio) == WRITE) ? "write" : "read", 2424b6d287fSNeilBrown (unsigned long long) bio->bi_sector, 2434b6d287fSNeilBrown (unsigned long long) bio->bi_sector + 2444b6d287fSNeilBrown (bio->bi_size >> 9) - 1); 2454b6d287fSNeilBrown 2466712ecf8SNeilBrown bio_endio(bio, 2471da177e4SLinus Torvalds test_bit(R1BIO_Uptodate, &r1_bio->state) ? 0 : -EIO); 2484b6d287fSNeilBrown } 2491da177e4SLinus Torvalds free_r1bio(r1_bio); 2501da177e4SLinus Torvalds } 2511da177e4SLinus Torvalds 2521da177e4SLinus Torvalds /* 2531da177e4SLinus Torvalds * Update disk head position estimator based on IRQ completion info. 2541da177e4SLinus Torvalds */ 2551da177e4SLinus Torvalds static inline void update_head_pos(int disk, r1bio_t *r1_bio) 2561da177e4SLinus Torvalds { 257070ec55dSNeilBrown conf_t *conf = r1_bio->mddev->private; 2581da177e4SLinus Torvalds 2591da177e4SLinus Torvalds conf->mirrors[disk].head_position = 2601da177e4SLinus Torvalds r1_bio->sector + (r1_bio->sectors); 2611da177e4SLinus Torvalds } 2621da177e4SLinus Torvalds 2636712ecf8SNeilBrown static void raid1_end_read_request(struct bio *bio, int error) 2641da177e4SLinus Torvalds { 2651da177e4SLinus Torvalds int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); 2667b92813cSH Hartley Sweeten r1bio_t *r1_bio = bio->bi_private; 2671da177e4SLinus Torvalds int mirror; 268070ec55dSNeilBrown conf_t *conf = r1_bio->mddev->private; 2691da177e4SLinus Torvalds 2701da177e4SLinus Torvalds mirror = r1_bio->read_disk; 2711da177e4SLinus Torvalds /* 2721da177e4SLinus Torvalds * this branch is our 'one mirror IO has finished' event handler: 2731da177e4SLinus Torvalds */ 274ddaf22abSNeilBrown update_head_pos(mirror, r1_bio); 275ddaf22abSNeilBrown 276220946c9SNeilBrown if (uptodate) 2771da177e4SLinus Torvalds set_bit(R1BIO_Uptodate, &r1_bio->state); 278dd00a99eSNeilBrown else { 279dd00a99eSNeilBrown /* If all other devices have failed, we want to return 280dd00a99eSNeilBrown * the error upwards rather than fail the last device. 281dd00a99eSNeilBrown * Here we redefine "uptodate" to mean "Don't want to retry" 282dd00a99eSNeilBrown */ 283dd00a99eSNeilBrown unsigned long flags; 284dd00a99eSNeilBrown spin_lock_irqsave(&conf->device_lock, flags); 285dd00a99eSNeilBrown if (r1_bio->mddev->degraded == conf->raid_disks || 286dd00a99eSNeilBrown (r1_bio->mddev->degraded == conf->raid_disks-1 && 287dd00a99eSNeilBrown !test_bit(Faulty, &conf->mirrors[mirror].rdev->flags))) 288dd00a99eSNeilBrown uptodate = 1; 289dd00a99eSNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 290dd00a99eSNeilBrown } 2911da177e4SLinus Torvalds 292dd00a99eSNeilBrown if (uptodate) 2931da177e4SLinus Torvalds raid_end_bio_io(r1_bio); 294dd00a99eSNeilBrown else { 2951da177e4SLinus Torvalds /* 2961da177e4SLinus Torvalds * oops, read error: 2971da177e4SLinus Torvalds */ 2981da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 2991da177e4SLinus Torvalds if (printk_ratelimit()) 3009dd1e2faSNeilBrown printk(KERN_ERR "md/raid1:%s: %s: rescheduling sector %llu\n", 3019dd1e2faSNeilBrown mdname(conf->mddev), 3021da177e4SLinus Torvalds bdevname(conf->mirrors[mirror].rdev->bdev,b), (unsigned long long)r1_bio->sector); 3031da177e4SLinus Torvalds reschedule_retry(r1_bio); 3041da177e4SLinus Torvalds } 3051da177e4SLinus Torvalds 3061da177e4SLinus Torvalds rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); 3071da177e4SLinus Torvalds } 3081da177e4SLinus Torvalds 3094e78064fSNeilBrown static void r1_bio_write_done(r1bio_t *r1_bio, int vcnt, struct bio_vec *bv, 3104e78064fSNeilBrown int behind) 3114e78064fSNeilBrown { 3124e78064fSNeilBrown if (atomic_dec_and_test(&r1_bio->remaining)) 3134e78064fSNeilBrown { 3144e78064fSNeilBrown /* it really is the end of this request */ 3154e78064fSNeilBrown if (test_bit(R1BIO_BehindIO, &r1_bio->state)) { 3164e78064fSNeilBrown /* free extra copy of the data pages */ 3174e78064fSNeilBrown int i = vcnt; 3184e78064fSNeilBrown while (i--) 3194e78064fSNeilBrown safe_put_page(bv[i].bv_page); 3204e78064fSNeilBrown } 3214e78064fSNeilBrown /* clear the bitmap if all writes complete successfully */ 3224e78064fSNeilBrown bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector, 3234e78064fSNeilBrown r1_bio->sectors, 3244e78064fSNeilBrown !test_bit(R1BIO_Degraded, &r1_bio->state), 3254e78064fSNeilBrown behind); 3264e78064fSNeilBrown md_write_end(r1_bio->mddev); 3274e78064fSNeilBrown raid_end_bio_io(r1_bio); 3284e78064fSNeilBrown } 3294e78064fSNeilBrown } 3304e78064fSNeilBrown 3316712ecf8SNeilBrown static void raid1_end_write_request(struct bio *bio, int error) 3321da177e4SLinus Torvalds { 3331da177e4SLinus Torvalds int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); 3347b92813cSH Hartley Sweeten r1bio_t *r1_bio = bio->bi_private; 335a9701a30SNeilBrown int mirror, behind = test_bit(R1BIO_BehindIO, &r1_bio->state); 336070ec55dSNeilBrown conf_t *conf = r1_bio->mddev->private; 33704b857f7SNeilBrown struct bio *to_put = NULL; 3381da177e4SLinus Torvalds 3391da177e4SLinus Torvalds 3401da177e4SLinus Torvalds for (mirror = 0; mirror < conf->raid_disks; mirror++) 3411da177e4SLinus Torvalds if (r1_bio->bios[mirror] == bio) 3421da177e4SLinus Torvalds break; 3431da177e4SLinus Torvalds 3441da177e4SLinus Torvalds /* 345e9c7469bSTejun Heo * 'one mirror IO has finished' event handler: 3461da177e4SLinus Torvalds */ 347a9701a30SNeilBrown r1_bio->bios[mirror] = NULL; 34804b857f7SNeilBrown to_put = bio; 349191ea9b2SNeilBrown if (!uptodate) { 3501da177e4SLinus Torvalds md_error(r1_bio->mddev, conf->mirrors[mirror].rdev); 351191ea9b2SNeilBrown /* an I/O failed, we can't clear the bitmap */ 352191ea9b2SNeilBrown set_bit(R1BIO_Degraded, &r1_bio->state); 353191ea9b2SNeilBrown } else 3541da177e4SLinus Torvalds /* 355e9c7469bSTejun Heo * Set R1BIO_Uptodate in our master bio, so that we 356e9c7469bSTejun Heo * will return a good error code for to the higher 357e9c7469bSTejun Heo * levels even if IO on some other mirrored buffer 358e9c7469bSTejun Heo * fails. 3591da177e4SLinus Torvalds * 360e9c7469bSTejun Heo * The 'master' represents the composite IO operation 361e9c7469bSTejun Heo * to user-side. So if something waits for IO, then it 362e9c7469bSTejun Heo * will wait for the 'master' bio. 3631da177e4SLinus Torvalds */ 3641da177e4SLinus Torvalds set_bit(R1BIO_Uptodate, &r1_bio->state); 3651da177e4SLinus Torvalds 3661da177e4SLinus Torvalds update_head_pos(mirror, r1_bio); 3671da177e4SLinus Torvalds 3684b6d287fSNeilBrown if (behind) { 3694b6d287fSNeilBrown if (test_bit(WriteMostly, &conf->mirrors[mirror].rdev->flags)) 3704b6d287fSNeilBrown atomic_dec(&r1_bio->behind_remaining); 3714b6d287fSNeilBrown 372e9c7469bSTejun Heo /* 373e9c7469bSTejun Heo * In behind mode, we ACK the master bio once the I/O 374e9c7469bSTejun Heo * has safely reached all non-writemostly 375e9c7469bSTejun Heo * disks. Setting the Returned bit ensures that this 376e9c7469bSTejun Heo * gets done only once -- we don't ever want to return 377e9c7469bSTejun Heo * -EIO here, instead we'll wait 378e9c7469bSTejun Heo */ 3794b6d287fSNeilBrown if (atomic_read(&r1_bio->behind_remaining) >= (atomic_read(&r1_bio->remaining)-1) && 3804b6d287fSNeilBrown test_bit(R1BIO_Uptodate, &r1_bio->state)) { 3814b6d287fSNeilBrown /* Maybe we can return now */ 3824b6d287fSNeilBrown if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) { 3834b6d287fSNeilBrown struct bio *mbio = r1_bio->master_bio; 3844b6d287fSNeilBrown PRINTK(KERN_DEBUG "raid1: behind end write sectors %llu-%llu\n", 3854b6d287fSNeilBrown (unsigned long long) mbio->bi_sector, 3864b6d287fSNeilBrown (unsigned long long) mbio->bi_sector + 3874b6d287fSNeilBrown (mbio->bi_size >> 9) - 1); 3886712ecf8SNeilBrown bio_endio(mbio, 0); 3894b6d287fSNeilBrown } 3904b6d287fSNeilBrown } 3914b6d287fSNeilBrown } 3925e7dd2abSNeilBrown rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); 393e9c7469bSTejun Heo 3941da177e4SLinus Torvalds /* 3951da177e4SLinus Torvalds * Let's see if all mirrored write operations have finished 3961da177e4SLinus Torvalds * already. 3971da177e4SLinus Torvalds */ 3984e78064fSNeilBrown r1_bio_write_done(r1_bio, bio->bi_vcnt, bio->bi_io_vec, behind); 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 { 421af3a2cd6SNeilBrown const sector_t 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)) { 437af3a2cd6SNeilBrown /* Choose the first operational 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 7464e78064fSNeilBrown /* duplicate the data pages for behind I/O 7474e78064fSNeilBrown * We return a list of bio_vec rather than just page pointers 7484e78064fSNeilBrown * as it makes freeing easier 7494e78064fSNeilBrown */ 7504e78064fSNeilBrown static struct bio_vec *alloc_behind_pages(struct bio *bio) 7514b6d287fSNeilBrown { 7524b6d287fSNeilBrown int i; 7534b6d287fSNeilBrown struct bio_vec *bvec; 7544e78064fSNeilBrown struct bio_vec *pages = kzalloc(bio->bi_vcnt * sizeof(struct bio_vec), 7554b6d287fSNeilBrown GFP_NOIO); 7564b6d287fSNeilBrown if (unlikely(!pages)) 7574b6d287fSNeilBrown goto do_sync_io; 7584b6d287fSNeilBrown 7594b6d287fSNeilBrown bio_for_each_segment(bvec, bio, i) { 7604e78064fSNeilBrown pages[i].bv_page = alloc_page(GFP_NOIO); 7614e78064fSNeilBrown if (unlikely(!pages[i].bv_page)) 7624b6d287fSNeilBrown goto do_sync_io; 7634e78064fSNeilBrown memcpy(kmap(pages[i].bv_page) + bvec->bv_offset, 7644b6d287fSNeilBrown kmap(bvec->bv_page) + bvec->bv_offset, bvec->bv_len); 7654e78064fSNeilBrown kunmap(pages[i].bv_page); 7664b6d287fSNeilBrown kunmap(bvec->bv_page); 7674b6d287fSNeilBrown } 7684b6d287fSNeilBrown 7694b6d287fSNeilBrown return pages; 7704b6d287fSNeilBrown 7714b6d287fSNeilBrown do_sync_io: 7724b6d287fSNeilBrown if (pages) 7734e78064fSNeilBrown for (i = 0; i < bio->bi_vcnt && pages[i].bv_page; i++) 7744e78064fSNeilBrown put_page(pages[i].bv_page); 7754b6d287fSNeilBrown kfree(pages); 7764b6d287fSNeilBrown PRINTK("%dB behind alloc failed, doing sync I/O\n", bio->bi_size); 7774b6d287fSNeilBrown return NULL; 7784b6d287fSNeilBrown } 7794b6d287fSNeilBrown 78021a52c6dSNeilBrown static int make_request(mddev_t *mddev, struct bio * bio) 7811da177e4SLinus Torvalds { 782070ec55dSNeilBrown conf_t *conf = mddev->private; 7831da177e4SLinus Torvalds mirror_info_t *mirror; 7841da177e4SLinus Torvalds r1bio_t *r1_bio; 7851da177e4SLinus Torvalds struct bio *read_bio; 786191ea9b2SNeilBrown int i, targets = 0, disks; 78784255d10SNeilBrown struct bitmap *bitmap; 788191ea9b2SNeilBrown unsigned long flags; 7894e78064fSNeilBrown struct bio_vec *behind_pages = NULL; 790a362357bSJens Axboe const int rw = bio_data_dir(bio); 7912c7d46ecSNeilBrown const unsigned long do_sync = (bio->bi_rw & REQ_SYNC); 792e9c7469bSTejun Heo const unsigned long do_flush_fua = (bio->bi_rw & (REQ_FLUSH | REQ_FUA)); 7936bfe0b49SDan Williams mdk_rdev_t *blocked_rdev; 794191ea9b2SNeilBrown 7951da177e4SLinus Torvalds /* 7961da177e4SLinus Torvalds * Register the new request and wait if the reconstruction 7971da177e4SLinus Torvalds * thread has put up a bar for new requests. 7981da177e4SLinus Torvalds * Continue immediately if no resync is active currently. 7991da177e4SLinus Torvalds */ 80062de608dSNeilBrown 8013d310eb7SNeilBrown md_write_start(mddev, bio); /* wait on superblock update early */ 8023d310eb7SNeilBrown 8036eef4b21SNeilBrown if (bio_data_dir(bio) == WRITE && 8046eef4b21SNeilBrown bio->bi_sector + bio->bi_size/512 > mddev->suspend_lo && 8056eef4b21SNeilBrown bio->bi_sector < mddev->suspend_hi) { 8066eef4b21SNeilBrown /* As the suspend_* range is controlled by 8076eef4b21SNeilBrown * userspace, we want an interruptible 8086eef4b21SNeilBrown * wait. 8096eef4b21SNeilBrown */ 8106eef4b21SNeilBrown DEFINE_WAIT(w); 8116eef4b21SNeilBrown for (;;) { 8126eef4b21SNeilBrown flush_signals(current); 8136eef4b21SNeilBrown prepare_to_wait(&conf->wait_barrier, 8146eef4b21SNeilBrown &w, TASK_INTERRUPTIBLE); 8156eef4b21SNeilBrown if (bio->bi_sector + bio->bi_size/512 <= mddev->suspend_lo || 8166eef4b21SNeilBrown bio->bi_sector >= mddev->suspend_hi) 8176eef4b21SNeilBrown break; 8186eef4b21SNeilBrown schedule(); 8196eef4b21SNeilBrown } 8206eef4b21SNeilBrown finish_wait(&conf->wait_barrier, &w); 8216eef4b21SNeilBrown } 82262de608dSNeilBrown 82317999be4SNeilBrown wait_barrier(conf); 8241da177e4SLinus Torvalds 82584255d10SNeilBrown bitmap = mddev->bitmap; 82684255d10SNeilBrown 8271da177e4SLinus Torvalds /* 8281da177e4SLinus Torvalds * make_request() can abort the operation when READA is being 8291da177e4SLinus Torvalds * used and no empty request is available. 8301da177e4SLinus Torvalds * 8311da177e4SLinus Torvalds */ 8321da177e4SLinus Torvalds r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO); 8331da177e4SLinus Torvalds 8341da177e4SLinus Torvalds r1_bio->master_bio = bio; 8351da177e4SLinus Torvalds r1_bio->sectors = bio->bi_size >> 9; 836191ea9b2SNeilBrown r1_bio->state = 0; 8371da177e4SLinus Torvalds r1_bio->mddev = mddev; 8381da177e4SLinus Torvalds r1_bio->sector = bio->bi_sector; 8391da177e4SLinus Torvalds 840a362357bSJens Axboe if (rw == READ) { 8411da177e4SLinus Torvalds /* 8421da177e4SLinus Torvalds * read balancing logic: 8431da177e4SLinus Torvalds */ 8441da177e4SLinus Torvalds int rdisk = read_balance(conf, r1_bio); 8451da177e4SLinus Torvalds 8461da177e4SLinus Torvalds if (rdisk < 0) { 8471da177e4SLinus Torvalds /* couldn't find anywhere to read from */ 8481da177e4SLinus Torvalds raid_end_bio_io(r1_bio); 8491da177e4SLinus Torvalds return 0; 8501da177e4SLinus Torvalds } 8511da177e4SLinus Torvalds mirror = conf->mirrors + rdisk; 8521da177e4SLinus Torvalds 853e555190dSNeilBrown if (test_bit(WriteMostly, &mirror->rdev->flags) && 854e555190dSNeilBrown bitmap) { 855e555190dSNeilBrown /* Reading from a write-mostly device must 856e555190dSNeilBrown * take care not to over-take any writes 857e555190dSNeilBrown * that are 'behind' 858e555190dSNeilBrown */ 859e555190dSNeilBrown wait_event(bitmap->behind_wait, 860e555190dSNeilBrown atomic_read(&bitmap->behind_writes) == 0); 861e555190dSNeilBrown } 8621da177e4SLinus Torvalds r1_bio->read_disk = rdisk; 8631da177e4SLinus Torvalds 8641da177e4SLinus Torvalds read_bio = bio_clone(bio, GFP_NOIO); 8651da177e4SLinus Torvalds 8661da177e4SLinus Torvalds r1_bio->bios[rdisk] = read_bio; 8671da177e4SLinus Torvalds 8681da177e4SLinus Torvalds read_bio->bi_sector = r1_bio->sector + mirror->rdev->data_offset; 8691da177e4SLinus Torvalds read_bio->bi_bdev = mirror->rdev->bdev; 8701da177e4SLinus Torvalds read_bio->bi_end_io = raid1_end_read_request; 8717b6d91daSChristoph Hellwig read_bio->bi_rw = READ | do_sync; 8721da177e4SLinus Torvalds read_bio->bi_private = r1_bio; 8731da177e4SLinus Torvalds 8741da177e4SLinus Torvalds generic_make_request(read_bio); 8751da177e4SLinus Torvalds return 0; 8761da177e4SLinus Torvalds } 8771da177e4SLinus Torvalds 8781da177e4SLinus Torvalds /* 8791da177e4SLinus Torvalds * WRITE: 8801da177e4SLinus Torvalds */ 8811da177e4SLinus Torvalds /* first select target devices under spinlock and 8821da177e4SLinus Torvalds * inc refcount on their rdev. Record them by setting 8831da177e4SLinus Torvalds * bios[x] to bio 8841da177e4SLinus Torvalds */ 8851da177e4SLinus Torvalds disks = conf->raid_disks; 8866bfe0b49SDan Williams retry_write: 8876bfe0b49SDan Williams blocked_rdev = NULL; 8881da177e4SLinus Torvalds rcu_read_lock(); 8891da177e4SLinus Torvalds for (i = 0; i < disks; i++) { 8906bfe0b49SDan Williams mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); 8916bfe0b49SDan Williams if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { 8926bfe0b49SDan Williams atomic_inc(&rdev->nr_pending); 8936bfe0b49SDan Williams blocked_rdev = rdev; 8946bfe0b49SDan Williams break; 8956bfe0b49SDan Williams } 8966bfe0b49SDan Williams if (rdev && !test_bit(Faulty, &rdev->flags)) { 8971da177e4SLinus Torvalds atomic_inc(&rdev->nr_pending); 898b2d444d7SNeilBrown if (test_bit(Faulty, &rdev->flags)) { 89903c902e1SNeilBrown rdev_dec_pending(rdev, mddev); 9001da177e4SLinus Torvalds r1_bio->bios[i] = NULL; 901964147d5SNeilBrown } else { 9021da177e4SLinus Torvalds r1_bio->bios[i] = bio; 903191ea9b2SNeilBrown targets++; 904964147d5SNeilBrown } 9051da177e4SLinus Torvalds } else 9061da177e4SLinus Torvalds r1_bio->bios[i] = NULL; 9071da177e4SLinus Torvalds } 9081da177e4SLinus Torvalds rcu_read_unlock(); 9091da177e4SLinus Torvalds 9106bfe0b49SDan Williams if (unlikely(blocked_rdev)) { 9116bfe0b49SDan Williams /* Wait for this device to become unblocked */ 9126bfe0b49SDan Williams int j; 9136bfe0b49SDan Williams 9146bfe0b49SDan Williams for (j = 0; j < i; j++) 9156bfe0b49SDan Williams if (r1_bio->bios[j]) 9166bfe0b49SDan Williams rdev_dec_pending(conf->mirrors[j].rdev, mddev); 9176bfe0b49SDan Williams 9186bfe0b49SDan Williams allow_barrier(conf); 9196bfe0b49SDan Williams md_wait_for_blocked_rdev(blocked_rdev, mddev); 9206bfe0b49SDan Williams wait_barrier(conf); 9216bfe0b49SDan Williams goto retry_write; 9226bfe0b49SDan Williams } 9236bfe0b49SDan Williams 9244b6d287fSNeilBrown BUG_ON(targets == 0); /* we never fail the last device */ 9254b6d287fSNeilBrown 926191ea9b2SNeilBrown if (targets < conf->raid_disks) { 927191ea9b2SNeilBrown /* array is degraded, we will not clear the bitmap 928191ea9b2SNeilBrown * on I/O completion (see raid1_end_write_request) */ 929191ea9b2SNeilBrown set_bit(R1BIO_Degraded, &r1_bio->state); 930191ea9b2SNeilBrown } 93106d91a5fSNeilBrown 932e555190dSNeilBrown /* do behind I/O ? 933e555190dSNeilBrown * Not if there are too many, or cannot allocate memory, 934e555190dSNeilBrown * or a reader on WriteMostly is waiting for behind writes 935e555190dSNeilBrown * to flush */ 9364b6d287fSNeilBrown if (bitmap && 93742a04b50SNeilBrown (atomic_read(&bitmap->behind_writes) 93842a04b50SNeilBrown < mddev->bitmap_info.max_write_behind) && 939e555190dSNeilBrown !waitqueue_active(&bitmap->behind_wait) && 9404b6d287fSNeilBrown (behind_pages = alloc_behind_pages(bio)) != NULL) 9414b6d287fSNeilBrown set_bit(R1BIO_BehindIO, &r1_bio->state); 9424b6d287fSNeilBrown 9434e78064fSNeilBrown atomic_set(&r1_bio->remaining, 1); 9444b6d287fSNeilBrown atomic_set(&r1_bio->behind_remaining, 0); 945191ea9b2SNeilBrown 9464e78064fSNeilBrown bitmap_startwrite(bitmap, bio->bi_sector, r1_bio->sectors, 9474e78064fSNeilBrown test_bit(R1BIO_BehindIO, &r1_bio->state)); 9481da177e4SLinus Torvalds for (i = 0; i < disks; i++) { 9491da177e4SLinus Torvalds struct bio *mbio; 9501da177e4SLinus Torvalds if (!r1_bio->bios[i]) 9511da177e4SLinus Torvalds continue; 9521da177e4SLinus Torvalds 9531da177e4SLinus Torvalds mbio = bio_clone(bio, GFP_NOIO); 9541da177e4SLinus Torvalds r1_bio->bios[i] = mbio; 9551da177e4SLinus Torvalds 9561da177e4SLinus Torvalds mbio->bi_sector = r1_bio->sector + conf->mirrors[i].rdev->data_offset; 9571da177e4SLinus Torvalds mbio->bi_bdev = conf->mirrors[i].rdev->bdev; 9581da177e4SLinus Torvalds mbio->bi_end_io = raid1_end_write_request; 959e9c7469bSTejun Heo mbio->bi_rw = WRITE | do_flush_fua | do_sync; 9601da177e4SLinus Torvalds mbio->bi_private = r1_bio; 9611da177e4SLinus Torvalds 9624b6d287fSNeilBrown if (behind_pages) { 9634b6d287fSNeilBrown struct bio_vec *bvec; 9644b6d287fSNeilBrown int j; 9654b6d287fSNeilBrown 9664b6d287fSNeilBrown /* Yes, I really want the '__' version so that 9674b6d287fSNeilBrown * we clear any unused pointer in the io_vec, rather 9684b6d287fSNeilBrown * than leave them unchanged. This is important 9694b6d287fSNeilBrown * because when we come to free the pages, we won't 9704b6d287fSNeilBrown * know the originial bi_idx, so we just free 9714b6d287fSNeilBrown * them all 9724b6d287fSNeilBrown */ 9734b6d287fSNeilBrown __bio_for_each_segment(bvec, mbio, j, 0) 9744e78064fSNeilBrown bvec->bv_page = behind_pages[j].bv_page; 9754b6d287fSNeilBrown if (test_bit(WriteMostly, &conf->mirrors[i].rdev->flags)) 9764b6d287fSNeilBrown atomic_inc(&r1_bio->behind_remaining); 9774b6d287fSNeilBrown } 9784b6d287fSNeilBrown 9791da177e4SLinus Torvalds atomic_inc(&r1_bio->remaining); 980191ea9b2SNeilBrown spin_lock_irqsave(&conf->device_lock, flags); 9814e78064fSNeilBrown bio_list_add(&conf->pending_bio_list, mbio); 982191ea9b2SNeilBrown blk_plug_device(mddev->queue); 983191ea9b2SNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 9844e78064fSNeilBrown } 9854e78064fSNeilBrown r1_bio_write_done(r1_bio, bio->bi_vcnt, behind_pages, behind_pages != NULL); 9864e78064fSNeilBrown kfree(behind_pages); /* the behind pages are attached to the bios now */ 987191ea9b2SNeilBrown 988a35e63efSNeilBrown /* In case raid1d snuck in to freeze_array */ 989a35e63efSNeilBrown wake_up(&conf->wait_barrier); 990a35e63efSNeilBrown 991e3881a68SLars Ellenberg if (do_sync) 992e3881a68SLars Ellenberg md_wakeup_thread(mddev->thread); 9931da177e4SLinus Torvalds 9941da177e4SLinus Torvalds return 0; 9951da177e4SLinus Torvalds } 9961da177e4SLinus Torvalds 9971da177e4SLinus Torvalds static void status(struct seq_file *seq, mddev_t *mddev) 9981da177e4SLinus Torvalds { 999070ec55dSNeilBrown conf_t *conf = mddev->private; 10001da177e4SLinus Torvalds int i; 10011da177e4SLinus Torvalds 10021da177e4SLinus Torvalds seq_printf(seq, " [%d/%d] [", conf->raid_disks, 100311ce99e6SNeilBrown conf->raid_disks - mddev->degraded); 1004ddac7c7eSNeilBrown rcu_read_lock(); 1005ddac7c7eSNeilBrown for (i = 0; i < conf->raid_disks; i++) { 1006ddac7c7eSNeilBrown mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); 10071da177e4SLinus Torvalds seq_printf(seq, "%s", 1008ddac7c7eSNeilBrown rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_"); 1009ddac7c7eSNeilBrown } 1010ddac7c7eSNeilBrown rcu_read_unlock(); 10111da177e4SLinus Torvalds seq_printf(seq, "]"); 10121da177e4SLinus Torvalds } 10131da177e4SLinus Torvalds 10141da177e4SLinus Torvalds 10151da177e4SLinus Torvalds static void error(mddev_t *mddev, mdk_rdev_t *rdev) 10161da177e4SLinus Torvalds { 10171da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 1018070ec55dSNeilBrown conf_t *conf = mddev->private; 10191da177e4SLinus Torvalds 10201da177e4SLinus Torvalds /* 10211da177e4SLinus Torvalds * If it is not operational, then we have already marked it as dead 10221da177e4SLinus Torvalds * else if it is the last working disks, ignore the error, let the 10231da177e4SLinus Torvalds * next level up know. 10241da177e4SLinus Torvalds * else mark the drive as failed 10251da177e4SLinus Torvalds */ 1026b2d444d7SNeilBrown if (test_bit(In_sync, &rdev->flags) 10274044ba58SNeilBrown && (conf->raid_disks - mddev->degraded) == 1) { 10281da177e4SLinus Torvalds /* 10291da177e4SLinus Torvalds * Don't fail the drive, act as though we were just a 10304044ba58SNeilBrown * normal single drive. 10314044ba58SNeilBrown * However don't try a recovery from this drive as 10324044ba58SNeilBrown * it is very likely to fail. 10331da177e4SLinus Torvalds */ 10344044ba58SNeilBrown mddev->recovery_disabled = 1; 10351da177e4SLinus Torvalds return; 10364044ba58SNeilBrown } 1037c04be0aaSNeilBrown if (test_and_clear_bit(In_sync, &rdev->flags)) { 1038c04be0aaSNeilBrown unsigned long flags; 1039c04be0aaSNeilBrown spin_lock_irqsave(&conf->device_lock, flags); 10401da177e4SLinus Torvalds mddev->degraded++; 1041dd00a99eSNeilBrown set_bit(Faulty, &rdev->flags); 1042c04be0aaSNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 10431da177e4SLinus Torvalds /* 10441da177e4SLinus Torvalds * if recovery is running, make sure it aborts. 10451da177e4SLinus Torvalds */ 1046dfc70645SNeilBrown set_bit(MD_RECOVERY_INTR, &mddev->recovery); 1047dd00a99eSNeilBrown } else 1048b2d444d7SNeilBrown set_bit(Faulty, &rdev->flags); 1049850b2b42SNeilBrown set_bit(MD_CHANGE_DEVS, &mddev->flags); 10509dd1e2faSNeilBrown printk(KERN_ALERT "md/raid1:%s: Disk failure on %s, disabling device.\n" 10519dd1e2faSNeilBrown KERN_ALERT "md/raid1:%s: Operation continuing on %d devices.\n", 10529dd1e2faSNeilBrown mdname(mddev), bdevname(rdev->bdev, b), 10539dd1e2faSNeilBrown mdname(mddev), conf->raid_disks - mddev->degraded); 10541da177e4SLinus Torvalds } 10551da177e4SLinus Torvalds 10561da177e4SLinus Torvalds static void print_conf(conf_t *conf) 10571da177e4SLinus Torvalds { 10581da177e4SLinus Torvalds int i; 10591da177e4SLinus Torvalds 10609dd1e2faSNeilBrown printk(KERN_DEBUG "RAID1 conf printout:\n"); 10611da177e4SLinus Torvalds if (!conf) { 10629dd1e2faSNeilBrown printk(KERN_DEBUG "(!conf)\n"); 10631da177e4SLinus Torvalds return; 10641da177e4SLinus Torvalds } 10659dd1e2faSNeilBrown printk(KERN_DEBUG " --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded, 10661da177e4SLinus Torvalds conf->raid_disks); 10671da177e4SLinus Torvalds 1068ddac7c7eSNeilBrown rcu_read_lock(); 10691da177e4SLinus Torvalds for (i = 0; i < conf->raid_disks; i++) { 10701da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 1071ddac7c7eSNeilBrown mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); 1072ddac7c7eSNeilBrown if (rdev) 10739dd1e2faSNeilBrown printk(KERN_DEBUG " disk %d, wo:%d, o:%d, dev:%s\n", 1074ddac7c7eSNeilBrown i, !test_bit(In_sync, &rdev->flags), 1075ddac7c7eSNeilBrown !test_bit(Faulty, &rdev->flags), 1076ddac7c7eSNeilBrown bdevname(rdev->bdev,b)); 10771da177e4SLinus Torvalds } 1078ddac7c7eSNeilBrown rcu_read_unlock(); 10791da177e4SLinus Torvalds } 10801da177e4SLinus Torvalds 10811da177e4SLinus Torvalds static void close_sync(conf_t *conf) 10821da177e4SLinus Torvalds { 108317999be4SNeilBrown wait_barrier(conf); 108417999be4SNeilBrown allow_barrier(conf); 10851da177e4SLinus Torvalds 10861da177e4SLinus Torvalds mempool_destroy(conf->r1buf_pool); 10871da177e4SLinus Torvalds conf->r1buf_pool = NULL; 10881da177e4SLinus Torvalds } 10891da177e4SLinus Torvalds 10901da177e4SLinus Torvalds static int raid1_spare_active(mddev_t *mddev) 10911da177e4SLinus Torvalds { 10921da177e4SLinus Torvalds int i; 10931da177e4SLinus Torvalds conf_t *conf = mddev->private; 10946b965620SNeilBrown int count = 0; 10956b965620SNeilBrown unsigned long flags; 10961da177e4SLinus Torvalds 10971da177e4SLinus Torvalds /* 10981da177e4SLinus Torvalds * Find all failed disks within the RAID1 configuration 1099ddac7c7eSNeilBrown * and mark them readable. 1100ddac7c7eSNeilBrown * Called under mddev lock, so rcu protection not needed. 11011da177e4SLinus Torvalds */ 11021da177e4SLinus Torvalds for (i = 0; i < conf->raid_disks; i++) { 1103ddac7c7eSNeilBrown mdk_rdev_t *rdev = conf->mirrors[i].rdev; 1104ddac7c7eSNeilBrown if (rdev 1105ddac7c7eSNeilBrown && !test_bit(Faulty, &rdev->flags) 1106c04be0aaSNeilBrown && !test_and_set_bit(In_sync, &rdev->flags)) { 11076b965620SNeilBrown count++; 1108e6ffbcb6SAdrian Drzewiecki sysfs_notify_dirent(rdev->sysfs_state); 11091da177e4SLinus Torvalds } 11101da177e4SLinus Torvalds } 11116b965620SNeilBrown spin_lock_irqsave(&conf->device_lock, flags); 11126b965620SNeilBrown mddev->degraded -= count; 11136b965620SNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 11141da177e4SLinus Torvalds 11151da177e4SLinus Torvalds print_conf(conf); 11166b965620SNeilBrown return count; 11171da177e4SLinus Torvalds } 11181da177e4SLinus Torvalds 11191da177e4SLinus Torvalds 11201da177e4SLinus Torvalds static int raid1_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) 11211da177e4SLinus Torvalds { 11221da177e4SLinus Torvalds conf_t *conf = mddev->private; 1123199050eaSNeil Brown int err = -EEXIST; 112441158c7eSNeilBrown int mirror = 0; 11251da177e4SLinus Torvalds mirror_info_t *p; 11266c2fce2eSNeil Brown int first = 0; 11276c2fce2eSNeil Brown int last = mddev->raid_disks - 1; 11281da177e4SLinus Torvalds 11296c2fce2eSNeil Brown if (rdev->raid_disk >= 0) 11306c2fce2eSNeil Brown first = last = rdev->raid_disk; 11316c2fce2eSNeil Brown 11326c2fce2eSNeil Brown for (mirror = first; mirror <= last; mirror++) 11331da177e4SLinus Torvalds if ( !(p=conf->mirrors+mirror)->rdev) { 11341da177e4SLinus Torvalds 11358f6c2e4bSMartin K. Petersen disk_stack_limits(mddev->gendisk, rdev->bdev, 11368f6c2e4bSMartin K. Petersen rdev->data_offset << 9); 1137627a2d3cSNeilBrown /* as we don't honour merge_bvec_fn, we must 1138627a2d3cSNeilBrown * never risk violating it, so limit 1139627a2d3cSNeilBrown * ->max_segments to one lying with a single 1140627a2d3cSNeilBrown * page, as a one page request is never in 1141627a2d3cSNeilBrown * violation. 11421da177e4SLinus Torvalds */ 1143627a2d3cSNeilBrown if (rdev->bdev->bd_disk->queue->merge_bvec_fn) { 1144627a2d3cSNeilBrown blk_queue_max_segments(mddev->queue, 1); 1145627a2d3cSNeilBrown blk_queue_segment_boundary(mddev->queue, 1146627a2d3cSNeilBrown PAGE_CACHE_SIZE - 1); 1147627a2d3cSNeilBrown } 11481da177e4SLinus Torvalds 11491da177e4SLinus Torvalds p->head_position = 0; 11501da177e4SLinus Torvalds rdev->raid_disk = mirror; 1151199050eaSNeil Brown err = 0; 11526aea114aSNeilBrown /* As all devices are equivalent, we don't need a full recovery 11536aea114aSNeilBrown * if this was recently any drive of the array 11546aea114aSNeilBrown */ 11556aea114aSNeilBrown if (rdev->saved_raid_disk < 0) 115641158c7eSNeilBrown conf->fullsync = 1; 1157d6065f7bSSuzanne Wood rcu_assign_pointer(p->rdev, rdev); 11581da177e4SLinus Torvalds break; 11591da177e4SLinus Torvalds } 1160ac5e7113SAndre Noll md_integrity_add_rdev(rdev, mddev); 11611da177e4SLinus Torvalds print_conf(conf); 1162199050eaSNeil Brown return err; 11631da177e4SLinus Torvalds } 11641da177e4SLinus Torvalds 11651da177e4SLinus Torvalds static int raid1_remove_disk(mddev_t *mddev, int number) 11661da177e4SLinus Torvalds { 11671da177e4SLinus Torvalds conf_t *conf = mddev->private; 11681da177e4SLinus Torvalds int err = 0; 11691da177e4SLinus Torvalds mdk_rdev_t *rdev; 11701da177e4SLinus Torvalds mirror_info_t *p = conf->mirrors+ number; 11711da177e4SLinus Torvalds 11721da177e4SLinus Torvalds print_conf(conf); 11731da177e4SLinus Torvalds rdev = p->rdev; 11741da177e4SLinus Torvalds if (rdev) { 1175b2d444d7SNeilBrown if (test_bit(In_sync, &rdev->flags) || 11761da177e4SLinus Torvalds atomic_read(&rdev->nr_pending)) { 11771da177e4SLinus Torvalds err = -EBUSY; 11781da177e4SLinus Torvalds goto abort; 11791da177e4SLinus Torvalds } 1180dfc70645SNeilBrown /* Only remove non-faulty devices is recovery 1181dfc70645SNeilBrown * is not possible. 1182dfc70645SNeilBrown */ 1183dfc70645SNeilBrown if (!test_bit(Faulty, &rdev->flags) && 1184dfc70645SNeilBrown mddev->degraded < conf->raid_disks) { 1185dfc70645SNeilBrown err = -EBUSY; 1186dfc70645SNeilBrown goto abort; 1187dfc70645SNeilBrown } 11881da177e4SLinus Torvalds p->rdev = NULL; 1189fbd568a3SPaul E. McKenney synchronize_rcu(); 11901da177e4SLinus Torvalds if (atomic_read(&rdev->nr_pending)) { 11911da177e4SLinus Torvalds /* lost the race, try later */ 11921da177e4SLinus Torvalds err = -EBUSY; 11931da177e4SLinus Torvalds p->rdev = rdev; 1194ac5e7113SAndre Noll goto abort; 11951da177e4SLinus Torvalds } 1196ac5e7113SAndre Noll md_integrity_register(mddev); 11971da177e4SLinus Torvalds } 11981da177e4SLinus Torvalds abort: 11991da177e4SLinus Torvalds 12001da177e4SLinus Torvalds print_conf(conf); 12011da177e4SLinus Torvalds return err; 12021da177e4SLinus Torvalds } 12031da177e4SLinus Torvalds 12041da177e4SLinus Torvalds 12056712ecf8SNeilBrown static void end_sync_read(struct bio *bio, int error) 12061da177e4SLinus Torvalds { 12077b92813cSH Hartley Sweeten r1bio_t *r1_bio = bio->bi_private; 1208d11c171eSNeilBrown int i; 12091da177e4SLinus Torvalds 1210d11c171eSNeilBrown for (i=r1_bio->mddev->raid_disks; i--; ) 1211d11c171eSNeilBrown if (r1_bio->bios[i] == bio) 1212d11c171eSNeilBrown break; 1213d11c171eSNeilBrown BUG_ON(i < 0); 1214d11c171eSNeilBrown update_head_pos(i, r1_bio); 12151da177e4SLinus Torvalds /* 12161da177e4SLinus Torvalds * we have read a block, now it needs to be re-written, 12171da177e4SLinus Torvalds * or re-read if the read failed. 12181da177e4SLinus Torvalds * We don't do much here, just schedule handling by raid1d 12191da177e4SLinus Torvalds */ 122069382e85SNeilBrown if (test_bit(BIO_UPTODATE, &bio->bi_flags)) 12211da177e4SLinus Torvalds set_bit(R1BIO_Uptodate, &r1_bio->state); 1222d11c171eSNeilBrown 1223d11c171eSNeilBrown if (atomic_dec_and_test(&r1_bio->remaining)) 12241da177e4SLinus Torvalds reschedule_retry(r1_bio); 12251da177e4SLinus Torvalds } 12261da177e4SLinus Torvalds 12276712ecf8SNeilBrown static void end_sync_write(struct bio *bio, int error) 12281da177e4SLinus Torvalds { 12291da177e4SLinus Torvalds int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); 12307b92813cSH Hartley Sweeten r1bio_t *r1_bio = bio->bi_private; 12311da177e4SLinus Torvalds mddev_t *mddev = r1_bio->mddev; 1232070ec55dSNeilBrown conf_t *conf = mddev->private; 12331da177e4SLinus Torvalds int i; 12341da177e4SLinus Torvalds int mirror=0; 12351da177e4SLinus Torvalds 12361da177e4SLinus Torvalds for (i = 0; i < conf->raid_disks; i++) 12371da177e4SLinus Torvalds if (r1_bio->bios[i] == bio) { 12381da177e4SLinus Torvalds mirror = i; 12391da177e4SLinus Torvalds break; 12401da177e4SLinus Torvalds } 12416b1117d5SNeilBrown if (!uptodate) { 124257dab0bdSNeilBrown sector_t sync_blocks = 0; 12436b1117d5SNeilBrown sector_t s = r1_bio->sector; 12446b1117d5SNeilBrown long sectors_to_go = r1_bio->sectors; 12456b1117d5SNeilBrown /* make sure these bits doesn't get cleared. */ 12466b1117d5SNeilBrown do { 12475e3db645SNeilBrown bitmap_end_sync(mddev->bitmap, s, 12486b1117d5SNeilBrown &sync_blocks, 1); 12496b1117d5SNeilBrown s += sync_blocks; 12506b1117d5SNeilBrown sectors_to_go -= sync_blocks; 12516b1117d5SNeilBrown } while (sectors_to_go > 0); 12521da177e4SLinus Torvalds md_error(mddev, conf->mirrors[mirror].rdev); 12536b1117d5SNeilBrown } 1254e3b9703eSNeilBrown 12551da177e4SLinus Torvalds update_head_pos(mirror, r1_bio); 12561da177e4SLinus Torvalds 12571da177e4SLinus Torvalds if (atomic_dec_and_test(&r1_bio->remaining)) { 125873d5c38aSNeilBrown sector_t s = r1_bio->sectors; 12591da177e4SLinus Torvalds put_buf(r1_bio); 126073d5c38aSNeilBrown md_done_sync(mddev, s, uptodate); 12611da177e4SLinus Torvalds } 12621da177e4SLinus Torvalds } 12631da177e4SLinus Torvalds 12641da177e4SLinus Torvalds static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) 12651da177e4SLinus Torvalds { 1266070ec55dSNeilBrown conf_t *conf = mddev->private; 12671da177e4SLinus Torvalds int i; 12681da177e4SLinus Torvalds int disks = conf->raid_disks; 12691da177e4SLinus Torvalds struct bio *bio, *wbio; 12701da177e4SLinus Torvalds 12711da177e4SLinus Torvalds bio = r1_bio->bios[r1_bio->read_disk]; 12721da177e4SLinus Torvalds 127369382e85SNeilBrown 1274d11c171eSNeilBrown if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { 1275d11c171eSNeilBrown /* We have read all readable devices. If we haven't 1276d11c171eSNeilBrown * got the block, then there is no hope left. 1277d11c171eSNeilBrown * If we have, then we want to do a comparison 1278d11c171eSNeilBrown * and skip the write if everything is the same. 1279d11c171eSNeilBrown * If any blocks failed to read, then we need to 1280d11c171eSNeilBrown * attempt an over-write 12811da177e4SLinus Torvalds */ 1282d11c171eSNeilBrown int primary; 1283d11c171eSNeilBrown if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) { 1284d11c171eSNeilBrown for (i=0; i<mddev->raid_disks; i++) 1285d11c171eSNeilBrown if (r1_bio->bios[i]->bi_end_io == end_sync_read) 1286d11c171eSNeilBrown md_error(mddev, conf->mirrors[i].rdev); 1287d11c171eSNeilBrown 1288d11c171eSNeilBrown md_done_sync(mddev, r1_bio->sectors, 1); 1289d11c171eSNeilBrown put_buf(r1_bio); 1290d11c171eSNeilBrown return; 1291d11c171eSNeilBrown } 1292d11c171eSNeilBrown for (primary=0; primary<mddev->raid_disks; primary++) 1293d11c171eSNeilBrown if (r1_bio->bios[primary]->bi_end_io == end_sync_read && 1294d11c171eSNeilBrown test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) { 1295d11c171eSNeilBrown r1_bio->bios[primary]->bi_end_io = NULL; 129603c902e1SNeilBrown rdev_dec_pending(conf->mirrors[primary].rdev, mddev); 1297d11c171eSNeilBrown break; 1298d11c171eSNeilBrown } 1299d11c171eSNeilBrown r1_bio->read_disk = primary; 1300d11c171eSNeilBrown for (i=0; i<mddev->raid_disks; i++) 1301ed456662SMike Accetta if (r1_bio->bios[i]->bi_end_io == end_sync_read) { 1302d11c171eSNeilBrown int j; 1303d11c171eSNeilBrown int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9); 1304d11c171eSNeilBrown struct bio *pbio = r1_bio->bios[primary]; 1305d11c171eSNeilBrown struct bio *sbio = r1_bio->bios[i]; 1306ed456662SMike Accetta 1307ed456662SMike Accetta if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) { 1308ed456662SMike Accetta for (j = vcnt; j-- ; ) { 1309ed456662SMike Accetta struct page *p, *s; 1310ed456662SMike Accetta p = pbio->bi_io_vec[j].bv_page; 1311ed456662SMike Accetta s = sbio->bi_io_vec[j].bv_page; 1312ed456662SMike Accetta if (memcmp(page_address(p), 1313ed456662SMike Accetta page_address(s), 1314d11c171eSNeilBrown PAGE_SIZE)) 1315d11c171eSNeilBrown break; 1316ed456662SMike Accetta } 1317ed456662SMike Accetta } else 1318ed456662SMike Accetta j = 0; 1319d11c171eSNeilBrown if (j >= 0) 1320d11c171eSNeilBrown mddev->resync_mismatches += r1_bio->sectors; 1321cf7a4416SNeilBrown if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery) 1322cf7a4416SNeilBrown && test_bit(BIO_UPTODATE, &sbio->bi_flags))) { 1323d11c171eSNeilBrown sbio->bi_end_io = NULL; 132403c902e1SNeilBrown rdev_dec_pending(conf->mirrors[i].rdev, mddev); 132503c902e1SNeilBrown } else { 1326d11c171eSNeilBrown /* fixup the bio for reuse */ 1327698b18c1SNeilBrown int size; 1328d11c171eSNeilBrown sbio->bi_vcnt = vcnt; 1329d11c171eSNeilBrown sbio->bi_size = r1_bio->sectors << 9; 1330d11c171eSNeilBrown sbio->bi_idx = 0; 1331d11c171eSNeilBrown sbio->bi_phys_segments = 0; 1332d11c171eSNeilBrown sbio->bi_flags &= ~(BIO_POOL_MASK - 1); 1333d11c171eSNeilBrown sbio->bi_flags |= 1 << BIO_UPTODATE; 1334d11c171eSNeilBrown sbio->bi_next = NULL; 1335d11c171eSNeilBrown sbio->bi_sector = r1_bio->sector + 1336d11c171eSNeilBrown conf->mirrors[i].rdev->data_offset; 1337d11c171eSNeilBrown sbio->bi_bdev = conf->mirrors[i].rdev->bdev; 1338698b18c1SNeilBrown size = sbio->bi_size; 1339698b18c1SNeilBrown for (j = 0; j < vcnt ; j++) { 1340698b18c1SNeilBrown struct bio_vec *bi; 1341698b18c1SNeilBrown bi = &sbio->bi_io_vec[j]; 1342698b18c1SNeilBrown bi->bv_offset = 0; 1343698b18c1SNeilBrown if (size > PAGE_SIZE) 1344698b18c1SNeilBrown bi->bv_len = PAGE_SIZE; 1345698b18c1SNeilBrown else 1346698b18c1SNeilBrown bi->bv_len = size; 1347698b18c1SNeilBrown size -= PAGE_SIZE; 1348698b18c1SNeilBrown memcpy(page_address(bi->bv_page), 13493eda22d1SNeilBrown page_address(pbio->bi_io_vec[j].bv_page), 13503eda22d1SNeilBrown PAGE_SIZE); 1351698b18c1SNeilBrown } 13523eda22d1SNeilBrown 1353d11c171eSNeilBrown } 1354d11c171eSNeilBrown } 1355d11c171eSNeilBrown } 13561da177e4SLinus Torvalds if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) { 135769382e85SNeilBrown /* ouch - failed to read all of that. 135869382e85SNeilBrown * Try some synchronous reads of other devices to get 135969382e85SNeilBrown * good data, much like with normal read errors. Only 1360ddac7c7eSNeilBrown * read into the pages we already have so we don't 136169382e85SNeilBrown * need to re-issue the read request. 136269382e85SNeilBrown * We don't need to freeze the array, because being in an 136369382e85SNeilBrown * active sync request, there is no normal IO, and 136469382e85SNeilBrown * no overlapping syncs. 13651da177e4SLinus Torvalds */ 136669382e85SNeilBrown sector_t sect = r1_bio->sector; 136769382e85SNeilBrown int sectors = r1_bio->sectors; 136869382e85SNeilBrown int idx = 0; 136969382e85SNeilBrown 137069382e85SNeilBrown while(sectors) { 137169382e85SNeilBrown int s = sectors; 137269382e85SNeilBrown int d = r1_bio->read_disk; 137369382e85SNeilBrown int success = 0; 137469382e85SNeilBrown mdk_rdev_t *rdev; 137569382e85SNeilBrown 137669382e85SNeilBrown if (s > (PAGE_SIZE>>9)) 137769382e85SNeilBrown s = PAGE_SIZE >> 9; 137869382e85SNeilBrown do { 137969382e85SNeilBrown if (r1_bio->bios[d]->bi_end_io == end_sync_read) { 1380ddac7c7eSNeilBrown /* No rcu protection needed here devices 1381ddac7c7eSNeilBrown * can only be removed when no resync is 1382ddac7c7eSNeilBrown * active, and resync is currently active 1383ddac7c7eSNeilBrown */ 138469382e85SNeilBrown rdev = conf->mirrors[d].rdev; 138569382e85SNeilBrown if (sync_page_io(rdev->bdev, 138669382e85SNeilBrown sect + rdev->data_offset, 138769382e85SNeilBrown s<<9, 138869382e85SNeilBrown bio->bi_io_vec[idx].bv_page, 138969382e85SNeilBrown READ)) { 139069382e85SNeilBrown success = 1; 139169382e85SNeilBrown break; 139269382e85SNeilBrown } 139369382e85SNeilBrown } 139469382e85SNeilBrown d++; 139569382e85SNeilBrown if (d == conf->raid_disks) 139669382e85SNeilBrown d = 0; 139769382e85SNeilBrown } while (!success && d != r1_bio->read_disk); 139869382e85SNeilBrown 139969382e85SNeilBrown if (success) { 1400097426f6SNeilBrown int start = d; 140169382e85SNeilBrown /* write it back and re-read */ 140269382e85SNeilBrown set_bit(R1BIO_Uptodate, &r1_bio->state); 140369382e85SNeilBrown while (d != r1_bio->read_disk) { 140469382e85SNeilBrown if (d == 0) 140569382e85SNeilBrown d = conf->raid_disks; 140669382e85SNeilBrown d--; 140769382e85SNeilBrown if (r1_bio->bios[d]->bi_end_io != end_sync_read) 140869382e85SNeilBrown continue; 140969382e85SNeilBrown rdev = conf->mirrors[d].rdev; 14104dbcdc75SNeilBrown atomic_add(s, &rdev->corrected_errors); 141169382e85SNeilBrown if (sync_page_io(rdev->bdev, 141269382e85SNeilBrown sect + rdev->data_offset, 141369382e85SNeilBrown s<<9, 141469382e85SNeilBrown bio->bi_io_vec[idx].bv_page, 1415097426f6SNeilBrown WRITE) == 0) 1416097426f6SNeilBrown md_error(mddev, rdev); 1417097426f6SNeilBrown } 1418097426f6SNeilBrown d = start; 1419097426f6SNeilBrown while (d != r1_bio->read_disk) { 1420097426f6SNeilBrown if (d == 0) 1421097426f6SNeilBrown d = conf->raid_disks; 1422097426f6SNeilBrown d--; 1423097426f6SNeilBrown if (r1_bio->bios[d]->bi_end_io != end_sync_read) 1424097426f6SNeilBrown continue; 1425097426f6SNeilBrown rdev = conf->mirrors[d].rdev; 1426097426f6SNeilBrown if (sync_page_io(rdev->bdev, 142769382e85SNeilBrown sect + rdev->data_offset, 142869382e85SNeilBrown s<<9, 142969382e85SNeilBrown bio->bi_io_vec[idx].bv_page, 1430097426f6SNeilBrown READ) == 0) 143169382e85SNeilBrown md_error(mddev, rdev); 143269382e85SNeilBrown } 143369382e85SNeilBrown } else { 14341da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 143569382e85SNeilBrown /* Cannot read from anywhere, array is toast */ 143669382e85SNeilBrown md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev); 14379dd1e2faSNeilBrown printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O read error" 14381da177e4SLinus Torvalds " for block %llu\n", 14399dd1e2faSNeilBrown mdname(mddev), 14401da177e4SLinus Torvalds bdevname(bio->bi_bdev, b), 14411da177e4SLinus Torvalds (unsigned long long)r1_bio->sector); 14421da177e4SLinus Torvalds md_done_sync(mddev, r1_bio->sectors, 0); 14431da177e4SLinus Torvalds put_buf(r1_bio); 14441da177e4SLinus Torvalds return; 14451da177e4SLinus Torvalds } 144669382e85SNeilBrown sectors -= s; 144769382e85SNeilBrown sect += s; 144869382e85SNeilBrown idx ++; 144969382e85SNeilBrown } 145069382e85SNeilBrown } 1451d11c171eSNeilBrown 1452d11c171eSNeilBrown /* 1453d11c171eSNeilBrown * schedule writes 1454d11c171eSNeilBrown */ 14551da177e4SLinus Torvalds atomic_set(&r1_bio->remaining, 1); 14561da177e4SLinus Torvalds for (i = 0; i < disks ; i++) { 14571da177e4SLinus Torvalds wbio = r1_bio->bios[i]; 14583e198f78SNeilBrown if (wbio->bi_end_io == NULL || 14593e198f78SNeilBrown (wbio->bi_end_io == end_sync_read && 14603e198f78SNeilBrown (i == r1_bio->read_disk || 14613e198f78SNeilBrown !test_bit(MD_RECOVERY_SYNC, &mddev->recovery)))) 14621da177e4SLinus Torvalds continue; 14631da177e4SLinus Torvalds 14643e198f78SNeilBrown wbio->bi_rw = WRITE; 14653e198f78SNeilBrown wbio->bi_end_io = end_sync_write; 14661da177e4SLinus Torvalds atomic_inc(&r1_bio->remaining); 14671da177e4SLinus Torvalds md_sync_acct(conf->mirrors[i].rdev->bdev, wbio->bi_size >> 9); 1468191ea9b2SNeilBrown 14691da177e4SLinus Torvalds generic_make_request(wbio); 14701da177e4SLinus Torvalds } 14711da177e4SLinus Torvalds 14721da177e4SLinus Torvalds if (atomic_dec_and_test(&r1_bio->remaining)) { 1473191ea9b2SNeilBrown /* if we're here, all write(s) have completed, so clean up */ 14741da177e4SLinus Torvalds md_done_sync(mddev, r1_bio->sectors, 1); 14751da177e4SLinus Torvalds put_buf(r1_bio); 14761da177e4SLinus Torvalds } 14771da177e4SLinus Torvalds } 14781da177e4SLinus Torvalds 14791da177e4SLinus Torvalds /* 14801da177e4SLinus Torvalds * This is a kernel thread which: 14811da177e4SLinus Torvalds * 14821da177e4SLinus Torvalds * 1. Retries failed read operations on working mirrors. 14831da177e4SLinus Torvalds * 2. Updates the raid superblock when problems encounter. 14841da177e4SLinus Torvalds * 3. Performs writes following reads for array syncronising. 14851da177e4SLinus Torvalds */ 14861da177e4SLinus Torvalds 1487867868fbSNeilBrown static void fix_read_error(conf_t *conf, int read_disk, 1488867868fbSNeilBrown sector_t sect, int sectors) 1489867868fbSNeilBrown { 1490867868fbSNeilBrown mddev_t *mddev = conf->mddev; 1491867868fbSNeilBrown while(sectors) { 1492867868fbSNeilBrown int s = sectors; 1493867868fbSNeilBrown int d = read_disk; 1494867868fbSNeilBrown int success = 0; 1495867868fbSNeilBrown int start; 1496867868fbSNeilBrown mdk_rdev_t *rdev; 1497867868fbSNeilBrown 1498867868fbSNeilBrown if (s > (PAGE_SIZE>>9)) 1499867868fbSNeilBrown s = PAGE_SIZE >> 9; 1500867868fbSNeilBrown 1501867868fbSNeilBrown do { 1502867868fbSNeilBrown /* Note: no rcu protection needed here 1503867868fbSNeilBrown * as this is synchronous in the raid1d thread 1504867868fbSNeilBrown * which is the thread that might remove 1505867868fbSNeilBrown * a device. If raid1d ever becomes multi-threaded.... 1506867868fbSNeilBrown */ 1507867868fbSNeilBrown rdev = conf->mirrors[d].rdev; 1508867868fbSNeilBrown if (rdev && 1509867868fbSNeilBrown test_bit(In_sync, &rdev->flags) && 1510867868fbSNeilBrown sync_page_io(rdev->bdev, 1511867868fbSNeilBrown sect + rdev->data_offset, 1512867868fbSNeilBrown s<<9, 1513867868fbSNeilBrown conf->tmppage, READ)) 1514867868fbSNeilBrown success = 1; 1515867868fbSNeilBrown else { 1516867868fbSNeilBrown d++; 1517867868fbSNeilBrown if (d == conf->raid_disks) 1518867868fbSNeilBrown d = 0; 1519867868fbSNeilBrown } 1520867868fbSNeilBrown } while (!success && d != read_disk); 1521867868fbSNeilBrown 1522867868fbSNeilBrown if (!success) { 1523867868fbSNeilBrown /* Cannot read from anywhere -- bye bye array */ 1524867868fbSNeilBrown md_error(mddev, conf->mirrors[read_disk].rdev); 1525867868fbSNeilBrown break; 1526867868fbSNeilBrown } 1527867868fbSNeilBrown /* write it back and re-read */ 1528867868fbSNeilBrown start = d; 1529867868fbSNeilBrown while (d != read_disk) { 1530867868fbSNeilBrown if (d==0) 1531867868fbSNeilBrown d = conf->raid_disks; 1532867868fbSNeilBrown d--; 1533867868fbSNeilBrown rdev = conf->mirrors[d].rdev; 1534867868fbSNeilBrown if (rdev && 1535867868fbSNeilBrown test_bit(In_sync, &rdev->flags)) { 1536867868fbSNeilBrown if (sync_page_io(rdev->bdev, 1537867868fbSNeilBrown sect + rdev->data_offset, 1538867868fbSNeilBrown s<<9, conf->tmppage, WRITE) 1539867868fbSNeilBrown == 0) 1540867868fbSNeilBrown /* Well, this device is dead */ 1541867868fbSNeilBrown md_error(mddev, rdev); 1542867868fbSNeilBrown } 1543867868fbSNeilBrown } 1544867868fbSNeilBrown d = start; 1545867868fbSNeilBrown while (d != read_disk) { 1546867868fbSNeilBrown char b[BDEVNAME_SIZE]; 1547867868fbSNeilBrown if (d==0) 1548867868fbSNeilBrown d = conf->raid_disks; 1549867868fbSNeilBrown d--; 1550867868fbSNeilBrown rdev = conf->mirrors[d].rdev; 1551867868fbSNeilBrown if (rdev && 1552867868fbSNeilBrown test_bit(In_sync, &rdev->flags)) { 1553867868fbSNeilBrown if (sync_page_io(rdev->bdev, 1554867868fbSNeilBrown sect + rdev->data_offset, 1555867868fbSNeilBrown s<<9, conf->tmppage, READ) 1556867868fbSNeilBrown == 0) 1557867868fbSNeilBrown /* Well, this device is dead */ 1558867868fbSNeilBrown md_error(mddev, rdev); 1559867868fbSNeilBrown else { 1560867868fbSNeilBrown atomic_add(s, &rdev->corrected_errors); 1561867868fbSNeilBrown printk(KERN_INFO 15629dd1e2faSNeilBrown "md/raid1:%s: read error corrected " 1563867868fbSNeilBrown "(%d sectors at %llu on %s)\n", 1564867868fbSNeilBrown mdname(mddev), s, 1565969b755aSRandy Dunlap (unsigned long long)(sect + 1566969b755aSRandy Dunlap rdev->data_offset), 1567867868fbSNeilBrown bdevname(rdev->bdev, b)); 1568867868fbSNeilBrown } 1569867868fbSNeilBrown } 1570867868fbSNeilBrown } 1571867868fbSNeilBrown sectors -= s; 1572867868fbSNeilBrown sect += s; 1573867868fbSNeilBrown } 1574867868fbSNeilBrown } 1575867868fbSNeilBrown 15761da177e4SLinus Torvalds static void raid1d(mddev_t *mddev) 15771da177e4SLinus Torvalds { 15781da177e4SLinus Torvalds r1bio_t *r1_bio; 15791da177e4SLinus Torvalds struct bio *bio; 15801da177e4SLinus Torvalds unsigned long flags; 1581070ec55dSNeilBrown conf_t *conf = mddev->private; 15821da177e4SLinus Torvalds struct list_head *head = &conf->retry_list; 15831da177e4SLinus Torvalds int unplug=0; 15841da177e4SLinus Torvalds mdk_rdev_t *rdev; 15851da177e4SLinus Torvalds 15861da177e4SLinus Torvalds md_check_recovery(mddev); 15871da177e4SLinus Torvalds 15881da177e4SLinus Torvalds for (;;) { 15891da177e4SLinus Torvalds char b[BDEVNAME_SIZE]; 1590a35e63efSNeilBrown 1591a35e63efSNeilBrown unplug += flush_pending_writes(conf); 1592a35e63efSNeilBrown 15931da177e4SLinus Torvalds spin_lock_irqsave(&conf->device_lock, flags); 1594a35e63efSNeilBrown if (list_empty(head)) { 1595191ea9b2SNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 15961da177e4SLinus Torvalds break; 1597a35e63efSNeilBrown } 15981da177e4SLinus Torvalds r1_bio = list_entry(head->prev, r1bio_t, retry_list); 15991da177e4SLinus Torvalds list_del(head->prev); 1600ddaf22abSNeilBrown conf->nr_queued--; 16011da177e4SLinus Torvalds spin_unlock_irqrestore(&conf->device_lock, flags); 16021da177e4SLinus Torvalds 16031da177e4SLinus Torvalds mddev = r1_bio->mddev; 1604070ec55dSNeilBrown conf = mddev->private; 16051da177e4SLinus Torvalds if (test_bit(R1BIO_IsSync, &r1_bio->state)) { 16061da177e4SLinus Torvalds sync_request_write(mddev, r1_bio); 16071da177e4SLinus Torvalds unplug = 1; 16081da177e4SLinus Torvalds } else { 16091da177e4SLinus Torvalds int disk; 1610ddaf22abSNeilBrown 1611ddaf22abSNeilBrown /* we got a read error. Maybe the drive is bad. Maybe just 1612ddaf22abSNeilBrown * the block and we can fix it. 1613ddaf22abSNeilBrown * We freeze all other IO, and try reading the block from 1614ddaf22abSNeilBrown * other devices. When we find one, we re-write 1615ddaf22abSNeilBrown * and check it that fixes the read error. 1616ddaf22abSNeilBrown * This is all done synchronously while the array is 1617ddaf22abSNeilBrown * frozen 1618ddaf22abSNeilBrown */ 1619867868fbSNeilBrown if (mddev->ro == 0) { 1620ddaf22abSNeilBrown freeze_array(conf); 1621867868fbSNeilBrown fix_read_error(conf, r1_bio->read_disk, 1622867868fbSNeilBrown r1_bio->sector, 1623867868fbSNeilBrown r1_bio->sectors); 1624ddaf22abSNeilBrown unfreeze_array(conf); 1625d0e26078SNeilBrown } else 1626d0e26078SNeilBrown md_error(mddev, 1627d0e26078SNeilBrown conf->mirrors[r1_bio->read_disk].rdev); 1628ddaf22abSNeilBrown 16291da177e4SLinus Torvalds bio = r1_bio->bios[r1_bio->read_disk]; 1630d0e26078SNeilBrown if ((disk=read_balance(conf, r1_bio)) == -1) { 16319dd1e2faSNeilBrown printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O" 16321da177e4SLinus Torvalds " read error for block %llu\n", 16339dd1e2faSNeilBrown mdname(mddev), 16341da177e4SLinus Torvalds bdevname(bio->bi_bdev,b), 16351da177e4SLinus Torvalds (unsigned long long)r1_bio->sector); 16361da177e4SLinus Torvalds raid_end_bio_io(r1_bio); 16371da177e4SLinus Torvalds } else { 16382c7d46ecSNeilBrown const unsigned long do_sync = r1_bio->master_bio->bi_rw & REQ_SYNC; 1639cf30a473SNeilBrown r1_bio->bios[r1_bio->read_disk] = 1640cf30a473SNeilBrown mddev->ro ? IO_BLOCKED : NULL; 16411da177e4SLinus Torvalds r1_bio->read_disk = disk; 16421da177e4SLinus Torvalds bio_put(bio); 16431da177e4SLinus Torvalds bio = bio_clone(r1_bio->master_bio, GFP_NOIO); 16441da177e4SLinus Torvalds r1_bio->bios[r1_bio->read_disk] = bio; 16451da177e4SLinus Torvalds rdev = conf->mirrors[disk].rdev; 16461da177e4SLinus Torvalds if (printk_ratelimit()) 16479dd1e2faSNeilBrown printk(KERN_ERR "md/raid1:%s: redirecting sector %llu to" 1648d754c5aeSNeilBrown " other mirror: %s\n", 16499dd1e2faSNeilBrown mdname(mddev), 1650d754c5aeSNeilBrown (unsigned long long)r1_bio->sector, 1651d754c5aeSNeilBrown bdevname(rdev->bdev,b)); 16521da177e4SLinus Torvalds bio->bi_sector = r1_bio->sector + rdev->data_offset; 16531da177e4SLinus Torvalds bio->bi_bdev = rdev->bdev; 16541da177e4SLinus Torvalds bio->bi_end_io = raid1_end_read_request; 16557b6d91daSChristoph Hellwig bio->bi_rw = READ | do_sync; 16561da177e4SLinus Torvalds bio->bi_private = r1_bio; 16571da177e4SLinus Torvalds unplug = 1; 16581da177e4SLinus Torvalds generic_make_request(bio); 16591da177e4SLinus Torvalds } 16601da177e4SLinus Torvalds } 16611d9d5241SNeilBrown cond_resched(); 16621da177e4SLinus Torvalds } 16631da177e4SLinus Torvalds if (unplug) 16641da177e4SLinus Torvalds unplug_slaves(mddev); 16651da177e4SLinus Torvalds } 16661da177e4SLinus Torvalds 16671da177e4SLinus Torvalds 16681da177e4SLinus Torvalds static int init_resync(conf_t *conf) 16691da177e4SLinus Torvalds { 16701da177e4SLinus Torvalds int buffs; 16711da177e4SLinus Torvalds 16721da177e4SLinus Torvalds buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE; 16739e77c485SEric Sesterhenn BUG_ON(conf->r1buf_pool); 16741da177e4SLinus Torvalds conf->r1buf_pool = mempool_create(buffs, r1buf_pool_alloc, r1buf_pool_free, 16751da177e4SLinus Torvalds conf->poolinfo); 16761da177e4SLinus Torvalds if (!conf->r1buf_pool) 16771da177e4SLinus Torvalds return -ENOMEM; 16781da177e4SLinus Torvalds conf->next_resync = 0; 16791da177e4SLinus Torvalds return 0; 16801da177e4SLinus Torvalds } 16811da177e4SLinus Torvalds 16821da177e4SLinus Torvalds /* 16831da177e4SLinus Torvalds * perform a "sync" on one "block" 16841da177e4SLinus Torvalds * 16851da177e4SLinus Torvalds * We need to make sure that no normal I/O request - particularly write 16861da177e4SLinus Torvalds * requests - conflict with active sync requests. 16871da177e4SLinus Torvalds * 16881da177e4SLinus Torvalds * This is achieved by tracking pending requests and a 'barrier' concept 16891da177e4SLinus Torvalds * that can be installed to exclude normal IO requests. 16901da177e4SLinus Torvalds */ 16911da177e4SLinus Torvalds 169257afd89fSNeilBrown static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster) 16931da177e4SLinus Torvalds { 1694070ec55dSNeilBrown conf_t *conf = mddev->private; 16951da177e4SLinus Torvalds r1bio_t *r1_bio; 16961da177e4SLinus Torvalds struct bio *bio; 16971da177e4SLinus Torvalds sector_t max_sector, nr_sectors; 16983e198f78SNeilBrown int disk = -1; 16991da177e4SLinus Torvalds int i; 17003e198f78SNeilBrown int wonly = -1; 17013e198f78SNeilBrown int write_targets = 0, read_targets = 0; 170257dab0bdSNeilBrown sector_t sync_blocks; 1703e3b9703eSNeilBrown int still_degraded = 0; 17041da177e4SLinus Torvalds 17051da177e4SLinus Torvalds if (!conf->r1buf_pool) 17061da177e4SLinus Torvalds if (init_resync(conf)) 170757afd89fSNeilBrown return 0; 17081da177e4SLinus Torvalds 170958c0fed4SAndre Noll max_sector = mddev->dev_sectors; 17101da177e4SLinus Torvalds if (sector_nr >= max_sector) { 1711191ea9b2SNeilBrown /* If we aborted, we need to abort the 1712191ea9b2SNeilBrown * sync on the 'current' bitmap chunk (there will 1713191ea9b2SNeilBrown * only be one in raid1 resync. 1714191ea9b2SNeilBrown * We can find the current addess in mddev->curr_resync 1715191ea9b2SNeilBrown */ 17166a806c51SNeilBrown if (mddev->curr_resync < max_sector) /* aborted */ 17176a806c51SNeilBrown bitmap_end_sync(mddev->bitmap, mddev->curr_resync, 1718191ea9b2SNeilBrown &sync_blocks, 1); 17196a806c51SNeilBrown else /* completed sync */ 1720191ea9b2SNeilBrown conf->fullsync = 0; 17216a806c51SNeilBrown 17226a806c51SNeilBrown bitmap_close_sync(mddev->bitmap); 17231da177e4SLinus Torvalds close_sync(conf); 17241da177e4SLinus Torvalds return 0; 17251da177e4SLinus Torvalds } 17261da177e4SLinus Torvalds 172707d84d10SNeilBrown if (mddev->bitmap == NULL && 172807d84d10SNeilBrown mddev->recovery_cp == MaxSector && 17296394cca5SNeilBrown !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && 173007d84d10SNeilBrown conf->fullsync == 0) { 173107d84d10SNeilBrown *skipped = 1; 173207d84d10SNeilBrown return max_sector - sector_nr; 173307d84d10SNeilBrown } 17346394cca5SNeilBrown /* before building a request, check if we can skip these blocks.. 17356394cca5SNeilBrown * This call the bitmap_start_sync doesn't actually record anything 17366394cca5SNeilBrown */ 1737e3b9703eSNeilBrown if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && 1738e5de485fSNeilBrown !conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { 1739191ea9b2SNeilBrown /* We can skip this block, and probably several more */ 1740191ea9b2SNeilBrown *skipped = 1; 1741191ea9b2SNeilBrown return sync_blocks; 1742191ea9b2SNeilBrown } 17431da177e4SLinus Torvalds /* 174417999be4SNeilBrown * If there is non-resync activity waiting for a turn, 174517999be4SNeilBrown * and resync is going fast enough, 174617999be4SNeilBrown * then let it though before starting on this new sync request. 17471da177e4SLinus Torvalds */ 174817999be4SNeilBrown if (!go_faster && conf->nr_waiting) 17491da177e4SLinus Torvalds msleep_interruptible(1000); 175017999be4SNeilBrown 1751b47490c9SNeilBrown bitmap_cond_end_sync(mddev->bitmap, sector_nr); 175217999be4SNeilBrown raise_barrier(conf); 175317999be4SNeilBrown 175417999be4SNeilBrown conf->next_resync = sector_nr; 17551da177e4SLinus Torvalds 17561da177e4SLinus Torvalds r1_bio = mempool_alloc(conf->r1buf_pool, GFP_NOIO); 17573e198f78SNeilBrown rcu_read_lock(); 17583e198f78SNeilBrown /* 17593e198f78SNeilBrown * If we get a correctably read error during resync or recovery, 17603e198f78SNeilBrown * we might want to read from a different device. So we 17613e198f78SNeilBrown * flag all drives that could conceivably be read from for READ, 17623e198f78SNeilBrown * and any others (which will be non-In_sync devices) for WRITE. 17633e198f78SNeilBrown * If a read fails, we try reading from something else for which READ 17643e198f78SNeilBrown * is OK. 17653e198f78SNeilBrown */ 17661da177e4SLinus Torvalds 17671da177e4SLinus Torvalds r1_bio->mddev = mddev; 17681da177e4SLinus Torvalds r1_bio->sector = sector_nr; 1769191ea9b2SNeilBrown r1_bio->state = 0; 17701da177e4SLinus Torvalds set_bit(R1BIO_IsSync, &r1_bio->state); 17711da177e4SLinus Torvalds 17721da177e4SLinus Torvalds for (i=0; i < conf->raid_disks; i++) { 17733e198f78SNeilBrown mdk_rdev_t *rdev; 17741da177e4SLinus Torvalds bio = r1_bio->bios[i]; 17751da177e4SLinus Torvalds 17761da177e4SLinus Torvalds /* take from bio_init */ 17771da177e4SLinus Torvalds bio->bi_next = NULL; 1778db8d9d35SNeilBrown bio->bi_flags &= ~(BIO_POOL_MASK-1); 17791da177e4SLinus Torvalds bio->bi_flags |= 1 << BIO_UPTODATE; 1780db8d9d35SNeilBrown bio->bi_comp_cpu = -1; 1781802ba064SNeilBrown bio->bi_rw = READ; 17821da177e4SLinus Torvalds bio->bi_vcnt = 0; 17831da177e4SLinus Torvalds bio->bi_idx = 0; 17841da177e4SLinus Torvalds bio->bi_phys_segments = 0; 17851da177e4SLinus Torvalds bio->bi_size = 0; 17861da177e4SLinus Torvalds bio->bi_end_io = NULL; 17871da177e4SLinus Torvalds bio->bi_private = NULL; 17881da177e4SLinus Torvalds 17893e198f78SNeilBrown rdev = rcu_dereference(conf->mirrors[i].rdev); 17903e198f78SNeilBrown if (rdev == NULL || 17913e198f78SNeilBrown test_bit(Faulty, &rdev->flags)) { 1792e3b9703eSNeilBrown still_degraded = 1; 1793e3b9703eSNeilBrown continue; 17943e198f78SNeilBrown } else if (!test_bit(In_sync, &rdev->flags)) { 17951da177e4SLinus Torvalds bio->bi_rw = WRITE; 17961da177e4SLinus Torvalds bio->bi_end_io = end_sync_write; 17971da177e4SLinus Torvalds write_targets ++; 17983e198f78SNeilBrown } else { 17993e198f78SNeilBrown /* may need to read from here */ 18003e198f78SNeilBrown bio->bi_rw = READ; 18013e198f78SNeilBrown bio->bi_end_io = end_sync_read; 18023e198f78SNeilBrown if (test_bit(WriteMostly, &rdev->flags)) { 18033e198f78SNeilBrown if (wonly < 0) 18043e198f78SNeilBrown wonly = i; 18053e198f78SNeilBrown } else { 18063e198f78SNeilBrown if (disk < 0) 18073e198f78SNeilBrown disk = i; 18083e198f78SNeilBrown } 18093e198f78SNeilBrown read_targets++; 18103e198f78SNeilBrown } 18113e198f78SNeilBrown atomic_inc(&rdev->nr_pending); 18123e198f78SNeilBrown bio->bi_sector = sector_nr + rdev->data_offset; 18133e198f78SNeilBrown bio->bi_bdev = rdev->bdev; 18141da177e4SLinus Torvalds bio->bi_private = r1_bio; 18151da177e4SLinus Torvalds } 18163e198f78SNeilBrown rcu_read_unlock(); 18173e198f78SNeilBrown if (disk < 0) 18183e198f78SNeilBrown disk = wonly; 18193e198f78SNeilBrown r1_bio->read_disk = disk; 1820191ea9b2SNeilBrown 18213e198f78SNeilBrown if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0) 18223e198f78SNeilBrown /* extra read targets are also write targets */ 18233e198f78SNeilBrown write_targets += read_targets-1; 18243e198f78SNeilBrown 18253e198f78SNeilBrown if (write_targets == 0 || read_targets == 0) { 18261da177e4SLinus Torvalds /* There is nowhere to write, so all non-sync 18271da177e4SLinus Torvalds * drives must be failed - so we are finished 18281da177e4SLinus Torvalds */ 182957afd89fSNeilBrown sector_t rv = max_sector - sector_nr; 183057afd89fSNeilBrown *skipped = 1; 18311da177e4SLinus Torvalds put_buf(r1_bio); 18321da177e4SLinus Torvalds return rv; 18331da177e4SLinus Torvalds } 18341da177e4SLinus Torvalds 1835c6207277SNeilBrown if (max_sector > mddev->resync_max) 1836c6207277SNeilBrown max_sector = mddev->resync_max; /* Don't do IO beyond here */ 18371da177e4SLinus Torvalds nr_sectors = 0; 1838289e99e8SNeilBrown sync_blocks = 0; 18391da177e4SLinus Torvalds do { 18401da177e4SLinus Torvalds struct page *page; 18411da177e4SLinus Torvalds int len = PAGE_SIZE; 18421da177e4SLinus Torvalds if (sector_nr + (len>>9) > max_sector) 18431da177e4SLinus Torvalds len = (max_sector - sector_nr) << 9; 18441da177e4SLinus Torvalds if (len == 0) 18451da177e4SLinus Torvalds break; 1846ab7a30c7SNeilBrown if (sync_blocks == 0) { 18476a806c51SNeilBrown if (!bitmap_start_sync(mddev->bitmap, sector_nr, 1848e3b9703eSNeilBrown &sync_blocks, still_degraded) && 1849e5de485fSNeilBrown !conf->fullsync && 1850e5de485fSNeilBrown !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) 1851191ea9b2SNeilBrown break; 18529e77c485SEric Sesterhenn BUG_ON(sync_blocks < (PAGE_SIZE>>9)); 18537571ae88SNeilBrown if ((len >> 9) > sync_blocks) 18546a806c51SNeilBrown len = sync_blocks<<9; 1855ab7a30c7SNeilBrown } 1856191ea9b2SNeilBrown 18571da177e4SLinus Torvalds for (i=0 ; i < conf->raid_disks; i++) { 18581da177e4SLinus Torvalds bio = r1_bio->bios[i]; 18591da177e4SLinus Torvalds if (bio->bi_end_io) { 1860d11c171eSNeilBrown page = bio->bi_io_vec[bio->bi_vcnt].bv_page; 18611da177e4SLinus Torvalds if (bio_add_page(bio, page, len, 0) == 0) { 18621da177e4SLinus Torvalds /* stop here */ 1863d11c171eSNeilBrown bio->bi_io_vec[bio->bi_vcnt].bv_page = page; 18641da177e4SLinus Torvalds while (i > 0) { 18651da177e4SLinus Torvalds i--; 18661da177e4SLinus Torvalds bio = r1_bio->bios[i]; 18676a806c51SNeilBrown if (bio->bi_end_io==NULL) 18686a806c51SNeilBrown continue; 18691da177e4SLinus Torvalds /* remove last page from this bio */ 18701da177e4SLinus Torvalds bio->bi_vcnt--; 18711da177e4SLinus Torvalds bio->bi_size -= len; 18721da177e4SLinus Torvalds bio->bi_flags &= ~(1<< BIO_SEG_VALID); 18731da177e4SLinus Torvalds } 18741da177e4SLinus Torvalds goto bio_full; 18751da177e4SLinus Torvalds } 18761da177e4SLinus Torvalds } 18771da177e4SLinus Torvalds } 18781da177e4SLinus Torvalds nr_sectors += len>>9; 18791da177e4SLinus Torvalds sector_nr += len>>9; 1880191ea9b2SNeilBrown sync_blocks -= (len>>9); 18811da177e4SLinus Torvalds } while (r1_bio->bios[disk]->bi_vcnt < RESYNC_PAGES); 18821da177e4SLinus Torvalds bio_full: 18831da177e4SLinus Torvalds r1_bio->sectors = nr_sectors; 18841da177e4SLinus Torvalds 1885d11c171eSNeilBrown /* For a user-requested sync, we read all readable devices and do a 1886d11c171eSNeilBrown * compare 1887d11c171eSNeilBrown */ 1888d11c171eSNeilBrown if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { 1889d11c171eSNeilBrown atomic_set(&r1_bio->remaining, read_targets); 1890d11c171eSNeilBrown for (i=0; i<conf->raid_disks; i++) { 1891d11c171eSNeilBrown bio = r1_bio->bios[i]; 1892d11c171eSNeilBrown if (bio->bi_end_io == end_sync_read) { 1893ddac7c7eSNeilBrown md_sync_acct(bio->bi_bdev, nr_sectors); 18941da177e4SLinus Torvalds generic_make_request(bio); 1895d11c171eSNeilBrown } 1896d11c171eSNeilBrown } 1897d11c171eSNeilBrown } else { 1898d11c171eSNeilBrown atomic_set(&r1_bio->remaining, 1); 1899d11c171eSNeilBrown bio = r1_bio->bios[r1_bio->read_disk]; 1900ddac7c7eSNeilBrown md_sync_acct(bio->bi_bdev, nr_sectors); 1901d11c171eSNeilBrown generic_make_request(bio); 1902d11c171eSNeilBrown 1903d11c171eSNeilBrown } 19041da177e4SLinus Torvalds return nr_sectors; 19051da177e4SLinus Torvalds } 19061da177e4SLinus Torvalds 190780c3a6ceSDan Williams static sector_t raid1_size(mddev_t *mddev, sector_t sectors, int raid_disks) 190880c3a6ceSDan Williams { 190980c3a6ceSDan Williams if (sectors) 191080c3a6ceSDan Williams return sectors; 191180c3a6ceSDan Williams 191280c3a6ceSDan Williams return mddev->dev_sectors; 191380c3a6ceSDan Williams } 191480c3a6ceSDan Williams 1915709ae487SNeilBrown static conf_t *setup_conf(mddev_t *mddev) 19161da177e4SLinus Torvalds { 19171da177e4SLinus Torvalds conf_t *conf; 1918709ae487SNeilBrown int i; 19191da177e4SLinus Torvalds mirror_info_t *disk; 19201da177e4SLinus Torvalds mdk_rdev_t *rdev; 1921709ae487SNeilBrown int err = -ENOMEM; 19221da177e4SLinus Torvalds 19239ffae0cfSNeilBrown conf = kzalloc(sizeof(conf_t), GFP_KERNEL); 19241da177e4SLinus Torvalds if (!conf) 1925709ae487SNeilBrown goto abort; 19261da177e4SLinus Torvalds 19279ffae0cfSNeilBrown conf->mirrors = kzalloc(sizeof(struct mirror_info)*mddev->raid_disks, 19281da177e4SLinus Torvalds GFP_KERNEL); 19291da177e4SLinus Torvalds if (!conf->mirrors) 1930709ae487SNeilBrown goto abort; 19311da177e4SLinus Torvalds 1932ddaf22abSNeilBrown conf->tmppage = alloc_page(GFP_KERNEL); 1933ddaf22abSNeilBrown if (!conf->tmppage) 1934709ae487SNeilBrown goto abort; 1935ddaf22abSNeilBrown 1936709ae487SNeilBrown conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL); 19371da177e4SLinus Torvalds if (!conf->poolinfo) 1938709ae487SNeilBrown goto abort; 19391da177e4SLinus Torvalds conf->poolinfo->raid_disks = mddev->raid_disks; 19401da177e4SLinus Torvalds conf->r1bio_pool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc, 19411da177e4SLinus Torvalds r1bio_pool_free, 19421da177e4SLinus Torvalds conf->poolinfo); 19431da177e4SLinus Torvalds if (!conf->r1bio_pool) 1944709ae487SNeilBrown goto abort; 1945709ae487SNeilBrown 1946ed9bfdf1SNeilBrown conf->poolinfo->mddev = mddev; 19471da177e4SLinus Torvalds 1948e7e72bf6SNeil Brown spin_lock_init(&conf->device_lock); 1949159ec1fcSCheng Renquan list_for_each_entry(rdev, &mddev->disks, same_set) { 1950709ae487SNeilBrown int disk_idx = rdev->raid_disk; 19511da177e4SLinus Torvalds if (disk_idx >= mddev->raid_disks 19521da177e4SLinus Torvalds || disk_idx < 0) 19531da177e4SLinus Torvalds continue; 19541da177e4SLinus Torvalds disk = conf->mirrors + disk_idx; 19551da177e4SLinus Torvalds 19561da177e4SLinus Torvalds disk->rdev = rdev; 19571da177e4SLinus Torvalds 19581da177e4SLinus Torvalds disk->head_position = 0; 19591da177e4SLinus Torvalds } 19601da177e4SLinus Torvalds conf->raid_disks = mddev->raid_disks; 19611da177e4SLinus Torvalds conf->mddev = mddev; 19621da177e4SLinus Torvalds INIT_LIST_HEAD(&conf->retry_list); 19631da177e4SLinus Torvalds 19641da177e4SLinus Torvalds spin_lock_init(&conf->resync_lock); 196517999be4SNeilBrown init_waitqueue_head(&conf->wait_barrier); 19661da177e4SLinus Torvalds 1967191ea9b2SNeilBrown bio_list_init(&conf->pending_bio_list); 1968191ea9b2SNeilBrown bio_list_init(&conf->flushing_bio_list); 1969191ea9b2SNeilBrown 1970709ae487SNeilBrown conf->last_used = -1; 19711da177e4SLinus Torvalds for (i = 0; i < conf->raid_disks; i++) { 19721da177e4SLinus Torvalds 19731da177e4SLinus Torvalds disk = conf->mirrors + i; 19741da177e4SLinus Torvalds 19755fd6c1dcSNeilBrown if (!disk->rdev || 19765fd6c1dcSNeilBrown !test_bit(In_sync, &disk->rdev->flags)) { 19771da177e4SLinus Torvalds disk->head_position = 0; 1978918f0238SNeilBrown if (disk->rdev) 197917571284SNeilBrown conf->fullsync = 1; 1980709ae487SNeilBrown } else if (conf->last_used < 0) 1981709ae487SNeilBrown /* 1982709ae487SNeilBrown * The first working device is used as a 1983709ae487SNeilBrown * starting point to read balancing. 1984709ae487SNeilBrown */ 1985709ae487SNeilBrown conf->last_used = i; 19861da177e4SLinus Torvalds } 1987709ae487SNeilBrown 1988709ae487SNeilBrown err = -EIO; 1989709ae487SNeilBrown if (conf->last_used < 0) { 19909dd1e2faSNeilBrown printk(KERN_ERR "md/raid1:%s: no operational mirrors\n", 199111ce99e6SNeilBrown mdname(mddev)); 1992709ae487SNeilBrown goto abort; 199311ce99e6SNeilBrown } 1994709ae487SNeilBrown err = -ENOMEM; 1995709ae487SNeilBrown conf->thread = md_register_thread(raid1d, mddev, NULL); 1996709ae487SNeilBrown if (!conf->thread) { 19971da177e4SLinus Torvalds printk(KERN_ERR 19989dd1e2faSNeilBrown "md/raid1:%s: couldn't allocate thread\n", 19991da177e4SLinus Torvalds mdname(mddev)); 2000709ae487SNeilBrown goto abort; 20011da177e4SLinus Torvalds } 2002191ea9b2SNeilBrown 2003709ae487SNeilBrown return conf; 2004709ae487SNeilBrown 2005709ae487SNeilBrown abort: 2006709ae487SNeilBrown if (conf) { 2007709ae487SNeilBrown if (conf->r1bio_pool) 2008709ae487SNeilBrown mempool_destroy(conf->r1bio_pool); 2009709ae487SNeilBrown kfree(conf->mirrors); 2010709ae487SNeilBrown safe_put_page(conf->tmppage); 2011709ae487SNeilBrown kfree(conf->poolinfo); 2012709ae487SNeilBrown kfree(conf); 2013709ae487SNeilBrown } 2014709ae487SNeilBrown return ERR_PTR(err); 2015709ae487SNeilBrown } 2016709ae487SNeilBrown 2017709ae487SNeilBrown static int run(mddev_t *mddev) 2018709ae487SNeilBrown { 2019709ae487SNeilBrown conf_t *conf; 2020709ae487SNeilBrown int i; 2021709ae487SNeilBrown mdk_rdev_t *rdev; 2022709ae487SNeilBrown 2023709ae487SNeilBrown if (mddev->level != 1) { 20249dd1e2faSNeilBrown printk(KERN_ERR "md/raid1:%s: raid level not set to mirroring (%d)\n", 2025709ae487SNeilBrown mdname(mddev), mddev->level); 2026709ae487SNeilBrown return -EIO; 2027709ae487SNeilBrown } 2028709ae487SNeilBrown if (mddev->reshape_position != MaxSector) { 20299dd1e2faSNeilBrown printk(KERN_ERR "md/raid1:%s: reshape_position set but not supported\n", 2030709ae487SNeilBrown mdname(mddev)); 2031709ae487SNeilBrown return -EIO; 2032709ae487SNeilBrown } 2033709ae487SNeilBrown /* 2034709ae487SNeilBrown * copy the already verified devices into our private RAID1 2035709ae487SNeilBrown * bookkeeping area. [whatever we allocate in run(), 2036709ae487SNeilBrown * should be freed in stop()] 2037709ae487SNeilBrown */ 2038709ae487SNeilBrown if (mddev->private == NULL) 2039709ae487SNeilBrown conf = setup_conf(mddev); 2040709ae487SNeilBrown else 2041709ae487SNeilBrown conf = mddev->private; 2042709ae487SNeilBrown 2043709ae487SNeilBrown if (IS_ERR(conf)) 2044709ae487SNeilBrown return PTR_ERR(conf); 2045709ae487SNeilBrown 2046709ae487SNeilBrown mddev->queue->queue_lock = &conf->device_lock; 2047709ae487SNeilBrown list_for_each_entry(rdev, &mddev->disks, same_set) { 2048709ae487SNeilBrown disk_stack_limits(mddev->gendisk, rdev->bdev, 2049709ae487SNeilBrown rdev->data_offset << 9); 2050709ae487SNeilBrown /* as we don't honour merge_bvec_fn, we must never risk 2051627a2d3cSNeilBrown * violating it, so limit ->max_segments to 1 lying within 2052627a2d3cSNeilBrown * a single page, as a one page request is never in violation. 2053709ae487SNeilBrown */ 2054627a2d3cSNeilBrown if (rdev->bdev->bd_disk->queue->merge_bvec_fn) { 2055627a2d3cSNeilBrown blk_queue_max_segments(mddev->queue, 1); 2056627a2d3cSNeilBrown blk_queue_segment_boundary(mddev->queue, 2057627a2d3cSNeilBrown PAGE_CACHE_SIZE - 1); 2058627a2d3cSNeilBrown } 2059709ae487SNeilBrown } 2060709ae487SNeilBrown 2061709ae487SNeilBrown mddev->degraded = 0; 2062709ae487SNeilBrown for (i=0; i < conf->raid_disks; i++) 2063709ae487SNeilBrown if (conf->mirrors[i].rdev == NULL || 2064709ae487SNeilBrown !test_bit(In_sync, &conf->mirrors[i].rdev->flags) || 2065709ae487SNeilBrown test_bit(Faulty, &conf->mirrors[i].rdev->flags)) 2066709ae487SNeilBrown mddev->degraded++; 2067709ae487SNeilBrown 2068709ae487SNeilBrown if (conf->raid_disks - mddev->degraded == 1) 2069709ae487SNeilBrown mddev->recovery_cp = MaxSector; 2070709ae487SNeilBrown 20718c6ac868SAndre Noll if (mddev->recovery_cp != MaxSector) 20729dd1e2faSNeilBrown printk(KERN_NOTICE "md/raid1:%s: not clean" 20738c6ac868SAndre Noll " -- starting background reconstruction\n", 20748c6ac868SAndre Noll mdname(mddev)); 20751da177e4SLinus Torvalds printk(KERN_INFO 20769dd1e2faSNeilBrown "md/raid1:%s: active with %d out of %d mirrors\n", 20771da177e4SLinus Torvalds mdname(mddev), mddev->raid_disks - mddev->degraded, 20781da177e4SLinus Torvalds mddev->raid_disks); 2079709ae487SNeilBrown 20801da177e4SLinus Torvalds /* 20811da177e4SLinus Torvalds * Ok, everything is just fine now 20821da177e4SLinus Torvalds */ 2083709ae487SNeilBrown mddev->thread = conf->thread; 2084709ae487SNeilBrown conf->thread = NULL; 2085709ae487SNeilBrown mddev->private = conf; 2086709ae487SNeilBrown 20871f403624SDan Williams md_set_array_sectors(mddev, raid1_size(mddev, 0, 0)); 20881da177e4SLinus Torvalds 20897a5febe9SNeilBrown mddev->queue->unplug_fn = raid1_unplug; 20900d129228SNeilBrown mddev->queue->backing_dev_info.congested_fn = raid1_congested; 20910d129228SNeilBrown mddev->queue->backing_dev_info.congested_data = mddev; 2092ac5e7113SAndre Noll md_integrity_register(mddev); 20931da177e4SLinus Torvalds return 0; 20941da177e4SLinus Torvalds } 20951da177e4SLinus Torvalds 20961da177e4SLinus Torvalds static int stop(mddev_t *mddev) 20971da177e4SLinus Torvalds { 2098070ec55dSNeilBrown conf_t *conf = mddev->private; 20994b6d287fSNeilBrown struct bitmap *bitmap = mddev->bitmap; 21004b6d287fSNeilBrown 21014b6d287fSNeilBrown /* wait for behind writes to complete */ 2102e555190dSNeilBrown if (bitmap && atomic_read(&bitmap->behind_writes) > 0) { 21039dd1e2faSNeilBrown printk(KERN_INFO "md/raid1:%s: behind writes in progress - waiting to stop.\n", 21049dd1e2faSNeilBrown mdname(mddev)); 21054b6d287fSNeilBrown /* need to kick something here to make sure I/O goes? */ 2106e555190dSNeilBrown wait_event(bitmap->behind_wait, 2107e555190dSNeilBrown atomic_read(&bitmap->behind_writes) == 0); 21084b6d287fSNeilBrown } 21091da177e4SLinus Torvalds 2110409c57f3SNeilBrown raise_barrier(conf); 2111409c57f3SNeilBrown lower_barrier(conf); 2112409c57f3SNeilBrown 21131da177e4SLinus Torvalds md_unregister_thread(mddev->thread); 21141da177e4SLinus Torvalds mddev->thread = NULL; 21151da177e4SLinus Torvalds blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ 21161da177e4SLinus Torvalds if (conf->r1bio_pool) 21171da177e4SLinus Torvalds mempool_destroy(conf->r1bio_pool); 21181da177e4SLinus Torvalds kfree(conf->mirrors); 21191da177e4SLinus Torvalds kfree(conf->poolinfo); 21201da177e4SLinus Torvalds kfree(conf); 21211da177e4SLinus Torvalds mddev->private = NULL; 21221da177e4SLinus Torvalds return 0; 21231da177e4SLinus Torvalds } 21241da177e4SLinus Torvalds 21251da177e4SLinus Torvalds static int raid1_resize(mddev_t *mddev, sector_t sectors) 21261da177e4SLinus Torvalds { 21271da177e4SLinus Torvalds /* no resync is happening, and there is enough space 21281da177e4SLinus Torvalds * on all devices, so we can resize. 21291da177e4SLinus Torvalds * We need to make sure resync covers any new space. 21301da177e4SLinus Torvalds * If the array is shrinking we should possibly wait until 21311da177e4SLinus Torvalds * any io in the removed space completes, but it hardly seems 21321da177e4SLinus Torvalds * worth it. 21331da177e4SLinus Torvalds */ 21341f403624SDan Williams md_set_array_sectors(mddev, raid1_size(mddev, sectors, 0)); 2135b522adcdSDan Williams if (mddev->array_sectors > raid1_size(mddev, sectors, 0)) 2136b522adcdSDan Williams return -EINVAL; 2137f233ea5cSAndre Noll set_capacity(mddev->gendisk, mddev->array_sectors); 2138449aad3eSNeilBrown revalidate_disk(mddev->gendisk); 2139b522adcdSDan Williams if (sectors > mddev->dev_sectors && 2140f233ea5cSAndre Noll mddev->recovery_cp == MaxSector) { 214158c0fed4SAndre Noll mddev->recovery_cp = mddev->dev_sectors; 21421da177e4SLinus Torvalds set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 21431da177e4SLinus Torvalds } 2144b522adcdSDan Williams mddev->dev_sectors = sectors; 21454b5c7ae8SNeilBrown mddev->resync_max_sectors = sectors; 21461da177e4SLinus Torvalds return 0; 21471da177e4SLinus Torvalds } 21481da177e4SLinus Torvalds 214963c70c4fSNeilBrown static int raid1_reshape(mddev_t *mddev) 21501da177e4SLinus Torvalds { 21511da177e4SLinus Torvalds /* We need to: 21521da177e4SLinus Torvalds * 1/ resize the r1bio_pool 21531da177e4SLinus Torvalds * 2/ resize conf->mirrors 21541da177e4SLinus Torvalds * 21551da177e4SLinus Torvalds * We allocate a new r1bio_pool if we can. 21561da177e4SLinus Torvalds * Then raise a device barrier and wait until all IO stops. 21571da177e4SLinus Torvalds * Then resize conf->mirrors and swap in the new r1bio pool. 21586ea9c07cSNeilBrown * 21596ea9c07cSNeilBrown * At the same time, we "pack" the devices so that all the missing 21606ea9c07cSNeilBrown * devices have the higher raid_disk numbers. 21611da177e4SLinus Torvalds */ 21621da177e4SLinus Torvalds mempool_t *newpool, *oldpool; 21631da177e4SLinus Torvalds struct pool_info *newpoolinfo; 21641da177e4SLinus Torvalds mirror_info_t *newmirrors; 2165070ec55dSNeilBrown conf_t *conf = mddev->private; 216663c70c4fSNeilBrown int cnt, raid_disks; 2167c04be0aaSNeilBrown unsigned long flags; 2168b5470dc5SDan Williams int d, d2, err; 21691da177e4SLinus Torvalds 217063c70c4fSNeilBrown /* Cannot change chunk_size, layout, or level */ 2171664e7c41SAndre Noll if (mddev->chunk_sectors != mddev->new_chunk_sectors || 217263c70c4fSNeilBrown mddev->layout != mddev->new_layout || 217363c70c4fSNeilBrown mddev->level != mddev->new_level) { 2174664e7c41SAndre Noll mddev->new_chunk_sectors = mddev->chunk_sectors; 217563c70c4fSNeilBrown mddev->new_layout = mddev->layout; 217663c70c4fSNeilBrown mddev->new_level = mddev->level; 217763c70c4fSNeilBrown return -EINVAL; 217863c70c4fSNeilBrown } 217963c70c4fSNeilBrown 2180b5470dc5SDan Williams err = md_allow_write(mddev); 2181b5470dc5SDan Williams if (err) 2182b5470dc5SDan Williams return err; 21832a2275d6SNeilBrown 218463c70c4fSNeilBrown raid_disks = mddev->raid_disks + mddev->delta_disks; 218563c70c4fSNeilBrown 21866ea9c07cSNeilBrown if (raid_disks < conf->raid_disks) { 21876ea9c07cSNeilBrown cnt=0; 21886ea9c07cSNeilBrown for (d= 0; d < conf->raid_disks; d++) 21891da177e4SLinus Torvalds if (conf->mirrors[d].rdev) 21906ea9c07cSNeilBrown cnt++; 21916ea9c07cSNeilBrown if (cnt > raid_disks) 21921da177e4SLinus Torvalds return -EBUSY; 21936ea9c07cSNeilBrown } 21941da177e4SLinus Torvalds 21951da177e4SLinus Torvalds newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL); 21961da177e4SLinus Torvalds if (!newpoolinfo) 21971da177e4SLinus Torvalds return -ENOMEM; 21981da177e4SLinus Torvalds newpoolinfo->mddev = mddev; 21991da177e4SLinus Torvalds newpoolinfo->raid_disks = raid_disks; 22001da177e4SLinus Torvalds 22011da177e4SLinus Torvalds newpool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc, 22021da177e4SLinus Torvalds r1bio_pool_free, newpoolinfo); 22031da177e4SLinus Torvalds if (!newpool) { 22041da177e4SLinus Torvalds kfree(newpoolinfo); 22051da177e4SLinus Torvalds return -ENOMEM; 22061da177e4SLinus Torvalds } 22079ffae0cfSNeilBrown newmirrors = kzalloc(sizeof(struct mirror_info) * raid_disks, GFP_KERNEL); 22081da177e4SLinus Torvalds if (!newmirrors) { 22091da177e4SLinus Torvalds kfree(newpoolinfo); 22101da177e4SLinus Torvalds mempool_destroy(newpool); 22111da177e4SLinus Torvalds return -ENOMEM; 22121da177e4SLinus Torvalds } 22131da177e4SLinus Torvalds 221417999be4SNeilBrown raise_barrier(conf); 22151da177e4SLinus Torvalds 22161da177e4SLinus Torvalds /* ok, everything is stopped */ 22171da177e4SLinus Torvalds oldpool = conf->r1bio_pool; 22181da177e4SLinus Torvalds conf->r1bio_pool = newpool; 22196ea9c07cSNeilBrown 2220a88aa786SNeilBrown for (d = d2 = 0; d < conf->raid_disks; d++) { 2221a88aa786SNeilBrown mdk_rdev_t *rdev = conf->mirrors[d].rdev; 2222a88aa786SNeilBrown if (rdev && rdev->raid_disk != d2) { 2223a88aa786SNeilBrown char nm[20]; 2224a88aa786SNeilBrown sprintf(nm, "rd%d", rdev->raid_disk); 2225a88aa786SNeilBrown sysfs_remove_link(&mddev->kobj, nm); 2226a88aa786SNeilBrown rdev->raid_disk = d2; 2227a88aa786SNeilBrown sprintf(nm, "rd%d", rdev->raid_disk); 2228a88aa786SNeilBrown sysfs_remove_link(&mddev->kobj, nm); 2229a88aa786SNeilBrown if (sysfs_create_link(&mddev->kobj, 2230a88aa786SNeilBrown &rdev->kobj, nm)) 2231a88aa786SNeilBrown printk(KERN_WARNING 22329dd1e2faSNeilBrown "md/raid1:%s: cannot register " 22339dd1e2faSNeilBrown "%s\n", 22349dd1e2faSNeilBrown mdname(mddev), nm); 2235a88aa786SNeilBrown } 2236a88aa786SNeilBrown if (rdev) 2237a88aa786SNeilBrown newmirrors[d2++].rdev = rdev; 22386ea9c07cSNeilBrown } 22391da177e4SLinus Torvalds kfree(conf->mirrors); 22401da177e4SLinus Torvalds conf->mirrors = newmirrors; 22411da177e4SLinus Torvalds kfree(conf->poolinfo); 22421da177e4SLinus Torvalds conf->poolinfo = newpoolinfo; 22431da177e4SLinus Torvalds 2244c04be0aaSNeilBrown spin_lock_irqsave(&conf->device_lock, flags); 22451da177e4SLinus Torvalds mddev->degraded += (raid_disks - conf->raid_disks); 2246c04be0aaSNeilBrown spin_unlock_irqrestore(&conf->device_lock, flags); 22471da177e4SLinus Torvalds conf->raid_disks = mddev->raid_disks = raid_disks; 224863c70c4fSNeilBrown mddev->delta_disks = 0; 22491da177e4SLinus Torvalds 22506ea9c07cSNeilBrown conf->last_used = 0; /* just make sure it is in-range */ 225117999be4SNeilBrown lower_barrier(conf); 22521da177e4SLinus Torvalds 22531da177e4SLinus Torvalds set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 22541da177e4SLinus Torvalds md_wakeup_thread(mddev->thread); 22551da177e4SLinus Torvalds 22561da177e4SLinus Torvalds mempool_destroy(oldpool); 22571da177e4SLinus Torvalds return 0; 22581da177e4SLinus Torvalds } 22591da177e4SLinus Torvalds 2260500af87aSNeilBrown static void raid1_quiesce(mddev_t *mddev, int state) 226136fa3063SNeilBrown { 2262070ec55dSNeilBrown conf_t *conf = mddev->private; 226336fa3063SNeilBrown 226436fa3063SNeilBrown switch(state) { 22656eef4b21SNeilBrown case 2: /* wake for suspend */ 22666eef4b21SNeilBrown wake_up(&conf->wait_barrier); 22676eef4b21SNeilBrown break; 22689e6603daSNeilBrown case 1: 226917999be4SNeilBrown raise_barrier(conf); 227036fa3063SNeilBrown break; 22719e6603daSNeilBrown case 0: 227217999be4SNeilBrown lower_barrier(conf); 227336fa3063SNeilBrown break; 227436fa3063SNeilBrown } 227536fa3063SNeilBrown } 227636fa3063SNeilBrown 2277709ae487SNeilBrown static void *raid1_takeover(mddev_t *mddev) 2278709ae487SNeilBrown { 2279709ae487SNeilBrown /* raid1 can take over: 2280709ae487SNeilBrown * raid5 with 2 devices, any layout or chunk size 2281709ae487SNeilBrown */ 2282709ae487SNeilBrown if (mddev->level == 5 && mddev->raid_disks == 2) { 2283709ae487SNeilBrown conf_t *conf; 2284709ae487SNeilBrown mddev->new_level = 1; 2285709ae487SNeilBrown mddev->new_layout = 0; 2286709ae487SNeilBrown mddev->new_chunk_sectors = 0; 2287709ae487SNeilBrown conf = setup_conf(mddev); 2288709ae487SNeilBrown if (!IS_ERR(conf)) 2289709ae487SNeilBrown conf->barrier = 1; 2290709ae487SNeilBrown return conf; 2291709ae487SNeilBrown } 2292709ae487SNeilBrown return ERR_PTR(-EINVAL); 2293709ae487SNeilBrown } 22941da177e4SLinus Torvalds 22952604b703SNeilBrown static struct mdk_personality raid1_personality = 22961da177e4SLinus Torvalds { 22971da177e4SLinus Torvalds .name = "raid1", 22982604b703SNeilBrown .level = 1, 22991da177e4SLinus Torvalds .owner = THIS_MODULE, 23001da177e4SLinus Torvalds .make_request = make_request, 23011da177e4SLinus Torvalds .run = run, 23021da177e4SLinus Torvalds .stop = stop, 23031da177e4SLinus Torvalds .status = status, 23041da177e4SLinus Torvalds .error_handler = error, 23051da177e4SLinus Torvalds .hot_add_disk = raid1_add_disk, 23061da177e4SLinus Torvalds .hot_remove_disk= raid1_remove_disk, 23071da177e4SLinus Torvalds .spare_active = raid1_spare_active, 23081da177e4SLinus Torvalds .sync_request = sync_request, 23091da177e4SLinus Torvalds .resize = raid1_resize, 231080c3a6ceSDan Williams .size = raid1_size, 231163c70c4fSNeilBrown .check_reshape = raid1_reshape, 231236fa3063SNeilBrown .quiesce = raid1_quiesce, 2313709ae487SNeilBrown .takeover = raid1_takeover, 23141da177e4SLinus Torvalds }; 23151da177e4SLinus Torvalds 23161da177e4SLinus Torvalds static int __init raid_init(void) 23171da177e4SLinus Torvalds { 23182604b703SNeilBrown return register_md_personality(&raid1_personality); 23191da177e4SLinus Torvalds } 23201da177e4SLinus Torvalds 23211da177e4SLinus Torvalds static void raid_exit(void) 23221da177e4SLinus Torvalds { 23232604b703SNeilBrown unregister_md_personality(&raid1_personality); 23241da177e4SLinus Torvalds } 23251da177e4SLinus Torvalds 23261da177e4SLinus Torvalds module_init(raid_init); 23271da177e4SLinus Torvalds module_exit(raid_exit); 23281da177e4SLinus Torvalds MODULE_LICENSE("GPL"); 23290efb9e61SNeilBrown MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD"); 23301da177e4SLinus Torvalds MODULE_ALIAS("md-personality-3"); /* RAID1 */ 2331d9d166c2SNeilBrown MODULE_ALIAS("md-raid1"); 23322604b703SNeilBrown MODULE_ALIAS("md-level-1"); 2333