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791 lines
20 KiB
791 lines
20 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
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/* |
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raid0.c : Multiple Devices driver for Linux |
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Copyright (C) 1994-96 Marc ZYNGIER |
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<[email protected]> or |
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<[email protected]> |
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Copyright (C) 1999, 2000 Ingo Molnar, Red Hat |
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RAID-0 management functions. |
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*/ |
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|
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#include <linux/blkdev.h> |
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#include <linux/seq_file.h> |
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#include <linux/module.h> |
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#include <linux/slab.h> |
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#include <trace/events/block.h> |
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#include "md.h" |
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#include "raid0.h" |
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#include "raid5.h" |
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static int default_layout = 0; |
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module_param(default_layout, int, 0644); |
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|
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#define UNSUPPORTED_MDDEV_FLAGS \ |
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((1L << MD_HAS_JOURNAL) | \ |
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(1L << MD_JOURNAL_CLEAN) | \ |
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(1L << MD_FAILFAST_SUPPORTED) |\ |
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(1L << MD_HAS_PPL) | \ |
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(1L << MD_HAS_MULTIPLE_PPLS)) |
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|
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/* |
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* inform the user of the raid configuration |
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*/ |
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static void dump_zones(struct mddev *mddev) |
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{ |
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int j, k; |
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sector_t zone_size = 0; |
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sector_t zone_start = 0; |
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char b[BDEVNAME_SIZE]; |
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struct r0conf *conf = mddev->private; |
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int raid_disks = conf->strip_zone[0].nb_dev; |
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pr_debug("md: RAID0 configuration for %s - %d zone%s\n", |
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mdname(mddev), |
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conf->nr_strip_zones, conf->nr_strip_zones==1?"":"s"); |
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for (j = 0; j < conf->nr_strip_zones; j++) { |
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char line[200]; |
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int len = 0; |
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for (k = 0; k < conf->strip_zone[j].nb_dev; k++) |
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len += snprintf(line+len, 200-len, "%s%s", k?"/":"", |
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bdevname(conf->devlist[j*raid_disks |
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+ k]->bdev, b)); |
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pr_debug("md: zone%d=[%s]\n", j, line); |
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zone_size = conf->strip_zone[j].zone_end - zone_start; |
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pr_debug(" zone-offset=%10lluKB, device-offset=%10lluKB, size=%10lluKB\n", |
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(unsigned long long)zone_start>>1, |
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(unsigned long long)conf->strip_zone[j].dev_start>>1, |
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(unsigned long long)zone_size>>1); |
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zone_start = conf->strip_zone[j].zone_end; |
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} |
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} |
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static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf) |
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{ |
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int i, c, err; |
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sector_t curr_zone_end, sectors; |
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struct md_rdev *smallest, *rdev1, *rdev2, *rdev, **dev; |
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struct strip_zone *zone; |
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int cnt; |
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char b[BDEVNAME_SIZE]; |
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char b2[BDEVNAME_SIZE]; |
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struct r0conf *conf = kzalloc(sizeof(*conf), GFP_KERNEL); |
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unsigned blksize = 512; |
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*private_conf = ERR_PTR(-ENOMEM); |
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if (!conf) |
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return -ENOMEM; |
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rdev_for_each(rdev1, mddev) { |
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pr_debug("md/raid0:%s: looking at %s\n", |
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mdname(mddev), |
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bdevname(rdev1->bdev, b)); |
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c = 0; |
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/* round size to chunk_size */ |
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sectors = rdev1->sectors; |
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sector_div(sectors, mddev->chunk_sectors); |
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rdev1->sectors = sectors * mddev->chunk_sectors; |
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blksize = max(blksize, queue_logical_block_size( |
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rdev1->bdev->bd_disk->queue)); |
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rdev_for_each(rdev2, mddev) { |
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pr_debug("md/raid0:%s: comparing %s(%llu)" |
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" with %s(%llu)\n", |
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mdname(mddev), |
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bdevname(rdev1->bdev,b), |
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(unsigned long long)rdev1->sectors, |
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bdevname(rdev2->bdev,b2), |
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(unsigned long long)rdev2->sectors); |
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if (rdev2 == rdev1) { |
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pr_debug("md/raid0:%s: END\n", |
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mdname(mddev)); |
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break; |
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} |
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if (rdev2->sectors == rdev1->sectors) { |
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/* |
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* Not unique, don't count it as a new |
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* group |
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*/ |
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pr_debug("md/raid0:%s: EQUAL\n", |
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mdname(mddev)); |
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c = 1; |
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break; |
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} |
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pr_debug("md/raid0:%s: NOT EQUAL\n", |
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mdname(mddev)); |
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} |
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if (!c) { |
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pr_debug("md/raid0:%s: ==> UNIQUE\n", |
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mdname(mddev)); |
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conf->nr_strip_zones++; |
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pr_debug("md/raid0:%s: %d zones\n", |
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mdname(mddev), conf->nr_strip_zones); |
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} |
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} |
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pr_debug("md/raid0:%s: FINAL %d zones\n", |
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mdname(mddev), conf->nr_strip_zones); |
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if (conf->nr_strip_zones == 1) { |
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conf->layout = RAID0_ORIG_LAYOUT; |
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} else if (mddev->layout == RAID0_ORIG_LAYOUT || |
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mddev->layout == RAID0_ALT_MULTIZONE_LAYOUT) { |
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conf->layout = mddev->layout; |
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} else if (default_layout == RAID0_ORIG_LAYOUT || |
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default_layout == RAID0_ALT_MULTIZONE_LAYOUT) { |
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conf->layout = default_layout; |
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} else { |
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pr_err("md/raid0:%s: cannot assemble multi-zone RAID0 with default_layout setting\n", |
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mdname(mddev)); |
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pr_err("md/raid0: please set raid0.default_layout to 1 or 2\n"); |
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err = -ENOTSUPP; |
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goto abort; |
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} |
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/* |
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* now since we have the hard sector sizes, we can make sure |
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* chunk size is a multiple of that sector size |
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*/ |
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if ((mddev->chunk_sectors << 9) % blksize) { |
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pr_warn("md/raid0:%s: chunk_size of %d not multiple of block size %d\n", |
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mdname(mddev), |
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mddev->chunk_sectors << 9, blksize); |
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err = -EINVAL; |
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goto abort; |
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} |
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err = -ENOMEM; |
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conf->strip_zone = kcalloc(conf->nr_strip_zones, |
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sizeof(struct strip_zone), |
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GFP_KERNEL); |
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if (!conf->strip_zone) |
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goto abort; |
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conf->devlist = kzalloc(array3_size(sizeof(struct md_rdev *), |
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conf->nr_strip_zones, |
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mddev->raid_disks), |
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GFP_KERNEL); |
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if (!conf->devlist) |
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goto abort; |
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/* The first zone must contain all devices, so here we check that |
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* there is a proper alignment of slots to devices and find them all |
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*/ |
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zone = &conf->strip_zone[0]; |
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cnt = 0; |
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smallest = NULL; |
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dev = conf->devlist; |
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err = -EINVAL; |
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rdev_for_each(rdev1, mddev) { |
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int j = rdev1->raid_disk; |
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if (mddev->level == 10) { |
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/* taking over a raid10-n2 array */ |
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j /= 2; |
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rdev1->new_raid_disk = j; |
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} |
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if (mddev->level == 1) { |
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/* taiking over a raid1 array- |
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* we have only one active disk |
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*/ |
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j = 0; |
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rdev1->new_raid_disk = j; |
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} |
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if (j < 0) { |
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pr_warn("md/raid0:%s: remove inactive devices before converting to RAID0\n", |
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mdname(mddev)); |
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goto abort; |
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} |
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if (j >= mddev->raid_disks) { |
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pr_warn("md/raid0:%s: bad disk number %d - aborting!\n", |
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mdname(mddev), j); |
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goto abort; |
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} |
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if (dev[j]) { |
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pr_warn("md/raid0:%s: multiple devices for %d - aborting!\n", |
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mdname(mddev), j); |
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goto abort; |
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} |
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dev[j] = rdev1; |
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if (!smallest || (rdev1->sectors < smallest->sectors)) |
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smallest = rdev1; |
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cnt++; |
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} |
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if (cnt != mddev->raid_disks) { |
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pr_warn("md/raid0:%s: too few disks (%d of %d) - aborting!\n", |
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mdname(mddev), cnt, mddev->raid_disks); |
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goto abort; |
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} |
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zone->nb_dev = cnt; |
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zone->zone_end = smallest->sectors * cnt; |
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curr_zone_end = zone->zone_end; |
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/* now do the other zones */ |
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for (i = 1; i < conf->nr_strip_zones; i++) |
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{ |
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int j; |
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zone = conf->strip_zone + i; |
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dev = conf->devlist + i * mddev->raid_disks; |
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pr_debug("md/raid0:%s: zone %d\n", mdname(mddev), i); |
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zone->dev_start = smallest->sectors; |
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smallest = NULL; |
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c = 0; |
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for (j=0; j<cnt; j++) { |
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rdev = conf->devlist[j]; |
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if (rdev->sectors <= zone->dev_start) { |
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pr_debug("md/raid0:%s: checking %s ... nope\n", |
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mdname(mddev), |
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bdevname(rdev->bdev, b)); |
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continue; |
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} |
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pr_debug("md/raid0:%s: checking %s ..." |
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" contained as device %d\n", |
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mdname(mddev), |
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bdevname(rdev->bdev, b), c); |
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dev[c] = rdev; |
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c++; |
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if (!smallest || rdev->sectors < smallest->sectors) { |
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smallest = rdev; |
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pr_debug("md/raid0:%s: (%llu) is smallest!.\n", |
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mdname(mddev), |
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(unsigned long long)rdev->sectors); |
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} |
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} |
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zone->nb_dev = c; |
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sectors = (smallest->sectors - zone->dev_start) * c; |
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pr_debug("md/raid0:%s: zone->nb_dev: %d, sectors: %llu\n", |
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mdname(mddev), |
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zone->nb_dev, (unsigned long long)sectors); |
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curr_zone_end += sectors; |
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zone->zone_end = curr_zone_end; |
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pr_debug("md/raid0:%s: current zone start: %llu\n", |
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mdname(mddev), |
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(unsigned long long)smallest->sectors); |
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} |
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pr_debug("md/raid0:%s: done.\n", mdname(mddev)); |
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*private_conf = conf; |
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return 0; |
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abort: |
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kfree(conf->strip_zone); |
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kfree(conf->devlist); |
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kfree(conf); |
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*private_conf = ERR_PTR(err); |
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return err; |
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} |
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/* Find the zone which holds a particular offset |
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* Update *sectorp to be an offset in that zone |
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*/ |
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static struct strip_zone *find_zone(struct r0conf *conf, |
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sector_t *sectorp) |
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{ |
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int i; |
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struct strip_zone *z = conf->strip_zone; |
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sector_t sector = *sectorp; |
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for (i = 0; i < conf->nr_strip_zones; i++) |
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if (sector < z[i].zone_end) { |
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if (i) |
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*sectorp = sector - z[i-1].zone_end; |
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return z + i; |
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} |
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BUG(); |
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} |
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/* |
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* remaps the bio to the target device. we separate two flows. |
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* power 2 flow and a general flow for the sake of performance |
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*/ |
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static struct md_rdev *map_sector(struct mddev *mddev, struct strip_zone *zone, |
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sector_t sector, sector_t *sector_offset) |
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{ |
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unsigned int sect_in_chunk; |
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sector_t chunk; |
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struct r0conf *conf = mddev->private; |
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int raid_disks = conf->strip_zone[0].nb_dev; |
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unsigned int chunk_sects = mddev->chunk_sectors; |
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if (is_power_of_2(chunk_sects)) { |
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int chunksect_bits = ffz(~chunk_sects); |
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/* find the sector offset inside the chunk */ |
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sect_in_chunk = sector & (chunk_sects - 1); |
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sector >>= chunksect_bits; |
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/* chunk in zone */ |
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chunk = *sector_offset; |
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/* quotient is the chunk in real device*/ |
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sector_div(chunk, zone->nb_dev << chunksect_bits); |
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} else{ |
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sect_in_chunk = sector_div(sector, chunk_sects); |
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chunk = *sector_offset; |
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sector_div(chunk, chunk_sects * zone->nb_dev); |
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} |
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/* |
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* position the bio over the real device |
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* real sector = chunk in device + starting of zone |
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* + the position in the chunk |
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*/ |
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*sector_offset = (chunk * chunk_sects) + sect_in_chunk; |
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return conf->devlist[(zone - conf->strip_zone)*raid_disks |
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+ sector_div(sector, zone->nb_dev)]; |
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} |
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static sector_t raid0_size(struct mddev *mddev, sector_t sectors, int raid_disks) |
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{ |
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sector_t array_sectors = 0; |
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struct md_rdev *rdev; |
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WARN_ONCE(sectors || raid_disks, |
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"%s does not support generic reshape\n", __func__); |
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rdev_for_each(rdev, mddev) |
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array_sectors += (rdev->sectors & |
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~(sector_t)(mddev->chunk_sectors-1)); |
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return array_sectors; |
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} |
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static void raid0_free(struct mddev *mddev, void *priv); |
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static int raid0_run(struct mddev *mddev) |
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{ |
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struct r0conf *conf; |
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int ret; |
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if (mddev->chunk_sectors == 0) { |
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pr_warn("md/raid0:%s: chunk size must be set.\n", mdname(mddev)); |
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return -EINVAL; |
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} |
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if (md_check_no_bitmap(mddev)) |
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return -EINVAL; |
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/* if private is not null, we are here after takeover */ |
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if (mddev->private == NULL) { |
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ret = create_strip_zones(mddev, &conf); |
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if (ret < 0) |
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return ret; |
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mddev->private = conf; |
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} |
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conf = mddev->private; |
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if (mddev->queue) { |
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struct md_rdev *rdev; |
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bool discard_supported = false; |
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blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors); |
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blk_queue_max_write_same_sectors(mddev->queue, mddev->chunk_sectors); |
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blk_queue_max_write_zeroes_sectors(mddev->queue, mddev->chunk_sectors); |
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blk_queue_max_discard_sectors(mddev->queue, UINT_MAX); |
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blk_queue_io_min(mddev->queue, mddev->chunk_sectors << 9); |
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blk_queue_io_opt(mddev->queue, |
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(mddev->chunk_sectors << 9) * mddev->raid_disks); |
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rdev_for_each(rdev, mddev) { |
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disk_stack_limits(mddev->gendisk, rdev->bdev, |
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rdev->data_offset << 9); |
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if (blk_queue_discard(bdev_get_queue(rdev->bdev))) |
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discard_supported = true; |
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} |
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if (!discard_supported) |
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blk_queue_flag_clear(QUEUE_FLAG_DISCARD, mddev->queue); |
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else |
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blk_queue_flag_set(QUEUE_FLAG_DISCARD, mddev->queue); |
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} |
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/* calculate array device size */ |
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md_set_array_sectors(mddev, raid0_size(mddev, 0, 0)); |
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pr_debug("md/raid0:%s: md_size is %llu sectors.\n", |
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mdname(mddev), |
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(unsigned long long)mddev->array_sectors); |
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dump_zones(mddev); |
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ret = md_integrity_register(mddev); |
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return ret; |
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} |
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static void raid0_free(struct mddev *mddev, void *priv) |
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{ |
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struct r0conf *conf = priv; |
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kfree(conf->strip_zone); |
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kfree(conf->devlist); |
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kfree(conf); |
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} |
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static void raid0_handle_discard(struct mddev *mddev, struct bio *bio) |
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{ |
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struct r0conf *conf = mddev->private; |
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struct strip_zone *zone; |
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sector_t start = bio->bi_iter.bi_sector; |
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sector_t end; |
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unsigned int stripe_size; |
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sector_t first_stripe_index, last_stripe_index; |
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sector_t start_disk_offset; |
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unsigned int start_disk_index; |
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sector_t end_disk_offset; |
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unsigned int end_disk_index; |
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unsigned int disk; |
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zone = find_zone(conf, &start); |
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|
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if (bio_end_sector(bio) > zone->zone_end) { |
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struct bio *split = bio_split(bio, |
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zone->zone_end - bio->bi_iter.bi_sector, GFP_NOIO, |
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&mddev->bio_set); |
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bio_chain(split, bio); |
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submit_bio_noacct(bio); |
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bio = split; |
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end = zone->zone_end; |
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} else |
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end = bio_end_sector(bio); |
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|
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if (zone != conf->strip_zone) |
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end = end - zone[-1].zone_end; |
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|
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/* Now start and end is the offset in zone */ |
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stripe_size = zone->nb_dev * mddev->chunk_sectors; |
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|
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first_stripe_index = start; |
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sector_div(first_stripe_index, stripe_size); |
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last_stripe_index = end; |
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sector_div(last_stripe_index, stripe_size); |
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|
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start_disk_index = (int)(start - first_stripe_index * stripe_size) / |
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mddev->chunk_sectors; |
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start_disk_offset = ((int)(start - first_stripe_index * stripe_size) % |
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mddev->chunk_sectors) + |
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first_stripe_index * mddev->chunk_sectors; |
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end_disk_index = (int)(end - last_stripe_index * stripe_size) / |
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mddev->chunk_sectors; |
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end_disk_offset = ((int)(end - last_stripe_index * stripe_size) % |
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mddev->chunk_sectors) + |
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last_stripe_index * mddev->chunk_sectors; |
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|
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for (disk = 0; disk < zone->nb_dev; disk++) { |
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sector_t dev_start, dev_end; |
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struct bio *discard_bio = NULL; |
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struct md_rdev *rdev; |
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|
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if (disk < start_disk_index) |
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dev_start = (first_stripe_index + 1) * |
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mddev->chunk_sectors; |
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else if (disk > start_disk_index) |
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dev_start = first_stripe_index * mddev->chunk_sectors; |
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else |
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dev_start = start_disk_offset; |
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|
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if (disk < end_disk_index) |
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dev_end = (last_stripe_index + 1) * mddev->chunk_sectors; |
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else if (disk > end_disk_index) |
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dev_end = last_stripe_index * mddev->chunk_sectors; |
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else |
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dev_end = end_disk_offset; |
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|
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if (dev_end <= dev_start) |
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continue; |
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|
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rdev = conf->devlist[(zone - conf->strip_zone) * |
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conf->strip_zone[0].nb_dev + disk]; |
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if (__blkdev_issue_discard(rdev->bdev, |
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dev_start + zone->dev_start + rdev->data_offset, |
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dev_end - dev_start, GFP_NOIO, 0, &discard_bio) || |
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!discard_bio) |
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continue; |
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bio_chain(discard_bio, bio); |
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bio_clone_blkg_association(discard_bio, bio); |
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if (mddev->gendisk) |
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trace_block_bio_remap(discard_bio, |
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disk_devt(mddev->gendisk), |
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bio->bi_iter.bi_sector); |
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submit_bio_noacct(discard_bio); |
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} |
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bio_endio(bio); |
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} |
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|
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static bool raid0_make_request(struct mddev *mddev, struct bio *bio) |
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{ |
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struct r0conf *conf = mddev->private; |
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struct strip_zone *zone; |
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struct md_rdev *tmp_dev; |
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sector_t bio_sector; |
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sector_t sector; |
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sector_t orig_sector; |
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unsigned chunk_sects; |
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unsigned sectors; |
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|
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if (unlikely(bio->bi_opf & REQ_PREFLUSH) |
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&& md_flush_request(mddev, bio)) |
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return true; |
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|
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if (unlikely((bio_op(bio) == REQ_OP_DISCARD))) { |
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raid0_handle_discard(mddev, bio); |
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return true; |
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} |
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|
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bio_sector = bio->bi_iter.bi_sector; |
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sector = bio_sector; |
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chunk_sects = mddev->chunk_sectors; |
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|
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sectors = chunk_sects - |
|
(likely(is_power_of_2(chunk_sects)) |
|
? (sector & (chunk_sects-1)) |
|
: sector_div(sector, chunk_sects)); |
|
|
|
/* Restore due to sector_div */ |
|
sector = bio_sector; |
|
|
|
if (sectors < bio_sectors(bio)) { |
|
struct bio *split = bio_split(bio, sectors, GFP_NOIO, |
|
&mddev->bio_set); |
|
bio_chain(split, bio); |
|
submit_bio_noacct(bio); |
|
bio = split; |
|
} |
|
|
|
orig_sector = sector; |
|
zone = find_zone(mddev->private, §or); |
|
switch (conf->layout) { |
|
case RAID0_ORIG_LAYOUT: |
|
tmp_dev = map_sector(mddev, zone, orig_sector, §or); |
|
break; |
|
case RAID0_ALT_MULTIZONE_LAYOUT: |
|
tmp_dev = map_sector(mddev, zone, sector, §or); |
|
break; |
|
default: |
|
WARN(1, "md/raid0:%s: Invalid layout\n", mdname(mddev)); |
|
bio_io_error(bio); |
|
return true; |
|
} |
|
|
|
if (unlikely(is_mddev_broken(tmp_dev, "raid0"))) { |
|
bio_io_error(bio); |
|
return true; |
|
} |
|
|
|
bio_set_dev(bio, tmp_dev->bdev); |
|
bio->bi_iter.bi_sector = sector + zone->dev_start + |
|
tmp_dev->data_offset; |
|
|
|
if (mddev->gendisk) |
|
trace_block_bio_remap(bio, disk_devt(mddev->gendisk), |
|
bio_sector); |
|
mddev_check_writesame(mddev, bio); |
|
mddev_check_write_zeroes(mddev, bio); |
|
submit_bio_noacct(bio); |
|
return true; |
|
} |
|
|
|
static void raid0_status(struct seq_file *seq, struct mddev *mddev) |
|
{ |
|
seq_printf(seq, " %dk chunks", mddev->chunk_sectors / 2); |
|
return; |
|
} |
|
|
|
static void *raid0_takeover_raid45(struct mddev *mddev) |
|
{ |
|
struct md_rdev *rdev; |
|
struct r0conf *priv_conf; |
|
|
|
if (mddev->degraded != 1) { |
|
pr_warn("md/raid0:%s: raid5 must be degraded! Degraded disks: %d\n", |
|
mdname(mddev), |
|
mddev->degraded); |
|
return ERR_PTR(-EINVAL); |
|
} |
|
|
|
rdev_for_each(rdev, mddev) { |
|
/* check slot number for a disk */ |
|
if (rdev->raid_disk == mddev->raid_disks-1) { |
|
pr_warn("md/raid0:%s: raid5 must have missing parity disk!\n", |
|
mdname(mddev)); |
|
return ERR_PTR(-EINVAL); |
|
} |
|
rdev->sectors = mddev->dev_sectors; |
|
} |
|
|
|
/* Set new parameters */ |
|
mddev->new_level = 0; |
|
mddev->new_layout = 0; |
|
mddev->new_chunk_sectors = mddev->chunk_sectors; |
|
mddev->raid_disks--; |
|
mddev->delta_disks = -1; |
|
/* make sure it will be not marked as dirty */ |
|
mddev->recovery_cp = MaxSector; |
|
mddev_clear_unsupported_flags(mddev, UNSUPPORTED_MDDEV_FLAGS); |
|
|
|
create_strip_zones(mddev, &priv_conf); |
|
|
|
return priv_conf; |
|
} |
|
|
|
static void *raid0_takeover_raid10(struct mddev *mddev) |
|
{ |
|
struct r0conf *priv_conf; |
|
|
|
/* Check layout: |
|
* - far_copies must be 1 |
|
* - near_copies must be 2 |
|
* - disks number must be even |
|
* - all mirrors must be already degraded |
|
*/ |
|
if (mddev->layout != ((1 << 8) + 2)) { |
|
pr_warn("md/raid0:%s:: Raid0 cannot takeover layout: 0x%x\n", |
|
mdname(mddev), |
|
mddev->layout); |
|
return ERR_PTR(-EINVAL); |
|
} |
|
if (mddev->raid_disks & 1) { |
|
pr_warn("md/raid0:%s: Raid0 cannot takeover Raid10 with odd disk number.\n", |
|
mdname(mddev)); |
|
return ERR_PTR(-EINVAL); |
|
} |
|
if (mddev->degraded != (mddev->raid_disks>>1)) { |
|
pr_warn("md/raid0:%s: All mirrors must be already degraded!\n", |
|
mdname(mddev)); |
|
return ERR_PTR(-EINVAL); |
|
} |
|
|
|
/* Set new parameters */ |
|
mddev->new_level = 0; |
|
mddev->new_layout = 0; |
|
mddev->new_chunk_sectors = mddev->chunk_sectors; |
|
mddev->delta_disks = - mddev->raid_disks / 2; |
|
mddev->raid_disks += mddev->delta_disks; |
|
mddev->degraded = 0; |
|
/* make sure it will be not marked as dirty */ |
|
mddev->recovery_cp = MaxSector; |
|
mddev_clear_unsupported_flags(mddev, UNSUPPORTED_MDDEV_FLAGS); |
|
|
|
create_strip_zones(mddev, &priv_conf); |
|
return priv_conf; |
|
} |
|
|
|
static void *raid0_takeover_raid1(struct mddev *mddev) |
|
{ |
|
struct r0conf *priv_conf; |
|
int chunksect; |
|
|
|
/* Check layout: |
|
* - (N - 1) mirror drives must be already faulty |
|
*/ |
|
if ((mddev->raid_disks - 1) != mddev->degraded) { |
|
pr_err("md/raid0:%s: (N - 1) mirrors drives must be already faulty!\n", |
|
mdname(mddev)); |
|
return ERR_PTR(-EINVAL); |
|
} |
|
|
|
/* |
|
* a raid1 doesn't have the notion of chunk size, so |
|
* figure out the largest suitable size we can use. |
|
*/ |
|
chunksect = 64 * 2; /* 64K by default */ |
|
|
|
/* The array must be an exact multiple of chunksize */ |
|
while (chunksect && (mddev->array_sectors & (chunksect - 1))) |
|
chunksect >>= 1; |
|
|
|
if ((chunksect << 9) < PAGE_SIZE) |
|
/* array size does not allow a suitable chunk size */ |
|
return ERR_PTR(-EINVAL); |
|
|
|
/* Set new parameters */ |
|
mddev->new_level = 0; |
|
mddev->new_layout = 0; |
|
mddev->new_chunk_sectors = chunksect; |
|
mddev->chunk_sectors = chunksect; |
|
mddev->delta_disks = 1 - mddev->raid_disks; |
|
mddev->raid_disks = 1; |
|
/* make sure it will be not marked as dirty */ |
|
mddev->recovery_cp = MaxSector; |
|
mddev_clear_unsupported_flags(mddev, UNSUPPORTED_MDDEV_FLAGS); |
|
|
|
create_strip_zones(mddev, &priv_conf); |
|
return priv_conf; |
|
} |
|
|
|
static void *raid0_takeover(struct mddev *mddev) |
|
{ |
|
/* raid0 can take over: |
|
* raid4 - if all data disks are active. |
|
* raid5 - providing it is Raid4 layout and one disk is faulty |
|
* raid10 - assuming we have all necessary active disks |
|
* raid1 - with (N -1) mirror drives faulty |
|
*/ |
|
|
|
if (mddev->bitmap) { |
|
pr_warn("md/raid0: %s: cannot takeover array with bitmap\n", |
|
mdname(mddev)); |
|
return ERR_PTR(-EBUSY); |
|
} |
|
if (mddev->level == 4) |
|
return raid0_takeover_raid45(mddev); |
|
|
|
if (mddev->level == 5) { |
|
if (mddev->layout == ALGORITHM_PARITY_N) |
|
return raid0_takeover_raid45(mddev); |
|
|
|
pr_warn("md/raid0:%s: Raid can only takeover Raid5 with layout: %d\n", |
|
mdname(mddev), ALGORITHM_PARITY_N); |
|
} |
|
|
|
if (mddev->level == 10) |
|
return raid0_takeover_raid10(mddev); |
|
|
|
if (mddev->level == 1) |
|
return raid0_takeover_raid1(mddev); |
|
|
|
pr_warn("Takeover from raid%i to raid0 not supported\n", |
|
mddev->level); |
|
|
|
return ERR_PTR(-EINVAL); |
|
} |
|
|
|
static void raid0_quiesce(struct mddev *mddev, int quiesce) |
|
{ |
|
} |
|
|
|
static struct md_personality raid0_personality= |
|
{ |
|
.name = "raid0", |
|
.level = 0, |
|
.owner = THIS_MODULE, |
|
.make_request = raid0_make_request, |
|
.run = raid0_run, |
|
.free = raid0_free, |
|
.status = raid0_status, |
|
.size = raid0_size, |
|
.takeover = raid0_takeover, |
|
.quiesce = raid0_quiesce, |
|
}; |
|
|
|
static int __init raid0_init (void) |
|
{ |
|
return register_md_personality (&raid0_personality); |
|
} |
|
|
|
static void raid0_exit (void) |
|
{ |
|
unregister_md_personality (&raid0_personality); |
|
} |
|
|
|
module_init(raid0_init); |
|
module_exit(raid0_exit); |
|
MODULE_LICENSE("GPL"); |
|
MODULE_DESCRIPTION("RAID0 (striping) personality for MD"); |
|
MODULE_ALIAS("md-personality-2"); /* RAID0 */ |
|
MODULE_ALIAS("md-raid0"); |
|
MODULE_ALIAS("md-level-0");
|
|
|