[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/drivers/md/raid0.c b/ap/os/linux/linux-3.4.x/drivers/md/raid0.c
new file mode 100644
index 0000000..06a0257
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/drivers/md/raid0.c
@@ -0,0 +1,740 @@
+/*
+ raid0.c : Multiple Devices driver for Linux
+ Copyright (C) 1994-96 Marc ZYNGIER
+ <zyngier@ufr-info-p7.ibp.fr> or
+ <maz@gloups.fdn.fr>
+ Copyright (C) 1999, 2000 Ingo Molnar, Red Hat
+
+
+ RAID-0 management functions.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ You should have received a copy of the GNU General Public License
+ (for example /usr/src/linux/COPYING); if not, write to the Free
+ Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include <linux/blkdev.h>
+#include <linux/seq_file.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include "md.h"
+#include "raid0.h"
+#include "raid5.h"
+
+static int raid0_congested(void *data, int bits)
+{
+ struct mddev *mddev = data;
+ struct r0conf *conf = mddev->private;
+ struct md_rdev **devlist = conf->devlist;
+ int raid_disks = conf->strip_zone[0].nb_dev;
+ int i, ret = 0;
+
+ if (mddev_congested(mddev, bits))
+ return 1;
+
+ for (i = 0; i < raid_disks && !ret ; i++) {
+ struct request_queue *q = bdev_get_queue(devlist[i]->bdev);
+
+ ret |= bdi_congested(&q->backing_dev_info, bits);
+ }
+ return ret;
+}
+
+/*
+ * inform the user of the raid configuration
+*/
+static void dump_zones(struct mddev *mddev)
+{
+ int j, k;
+ sector_t zone_size = 0;
+ sector_t zone_start = 0;
+ char b[BDEVNAME_SIZE];
+ struct r0conf *conf = mddev->private;
+ int raid_disks = conf->strip_zone[0].nb_dev;
+ printk(KERN_INFO "md: RAID0 configuration for %s - %d zone%s\n",
+ mdname(mddev),
+ conf->nr_strip_zones, conf->nr_strip_zones==1?"":"s");
+ for (j = 0; j < conf->nr_strip_zones; j++) {
+ printk(KERN_INFO "md: zone%d=[", j);
+ for (k = 0; k < conf->strip_zone[j].nb_dev; k++)
+ printk(KERN_CONT "%s%s", k?"/":"",
+ bdevname(conf->devlist[j*raid_disks
+ + k]->bdev, b));
+ printk(KERN_CONT "]\n");
+
+ zone_size = conf->strip_zone[j].zone_end - zone_start;
+ printk(KERN_INFO " zone-offset=%10lluKB, "
+ "device-offset=%10lluKB, size=%10lluKB\n",
+ (unsigned long long)zone_start>>1,
+ (unsigned long long)conf->strip_zone[j].dev_start>>1,
+ (unsigned long long)zone_size>>1);
+ zone_start = conf->strip_zone[j].zone_end;
+ }
+ printk(KERN_INFO "\n");
+}
+
+static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf)
+{
+ int i, c, err;
+ sector_t curr_zone_end, sectors;
+ struct md_rdev *smallest, *rdev1, *rdev2, *rdev, **dev;
+ struct strip_zone *zone;
+ int cnt;
+ char b[BDEVNAME_SIZE];
+ char b2[BDEVNAME_SIZE];
+ struct r0conf *conf = kzalloc(sizeof(*conf), GFP_KERNEL);
+
+ if (!conf)
+ return -ENOMEM;
+ rdev_for_each(rdev1, mddev) {
+ pr_debug("md/raid0:%s: looking at %s\n",
+ mdname(mddev),
+ bdevname(rdev1->bdev, b));
+ c = 0;
+
+ /* round size to chunk_size */
+ sectors = rdev1->sectors;
+ sector_div(sectors, mddev->chunk_sectors);
+ rdev1->sectors = sectors * mddev->chunk_sectors;
+
+ rdev_for_each(rdev2, mddev) {
+ pr_debug("md/raid0:%s: comparing %s(%llu)"
+ " with %s(%llu)\n",
+ mdname(mddev),
+ bdevname(rdev1->bdev,b),
+ (unsigned long long)rdev1->sectors,
+ bdevname(rdev2->bdev,b2),
+ (unsigned long long)rdev2->sectors);
+ if (rdev2 == rdev1) {
+ pr_debug("md/raid0:%s: END\n",
+ mdname(mddev));
+ break;
+ }
+ if (rdev2->sectors == rdev1->sectors) {
+ /*
+ * Not unique, don't count it as a new
+ * group
+ */
+ pr_debug("md/raid0:%s: EQUAL\n",
+ mdname(mddev));
+ c = 1;
+ break;
+ }
+ pr_debug("md/raid0:%s: NOT EQUAL\n",
+ mdname(mddev));
+ }
+ if (!c) {
+ pr_debug("md/raid0:%s: ==> UNIQUE\n",
+ mdname(mddev));
+ conf->nr_strip_zones++;
+ pr_debug("md/raid0:%s: %d zones\n",
+ mdname(mddev), conf->nr_strip_zones);
+ }
+ }
+ pr_debug("md/raid0:%s: FINAL %d zones\n",
+ mdname(mddev), conf->nr_strip_zones);
+ err = -ENOMEM;
+ conf->strip_zone = kzalloc(sizeof(struct strip_zone)*
+ conf->nr_strip_zones, GFP_KERNEL);
+ if (!conf->strip_zone)
+ goto abort;
+ conf->devlist = kzalloc(sizeof(struct md_rdev*)*
+ conf->nr_strip_zones*mddev->raid_disks,
+ GFP_KERNEL);
+ if (!conf->devlist)
+ goto abort;
+
+ /* The first zone must contain all devices, so here we check that
+ * there is a proper alignment of slots to devices and find them all
+ */
+ zone = &conf->strip_zone[0];
+ cnt = 0;
+ smallest = NULL;
+ dev = conf->devlist;
+ err = -EINVAL;
+ rdev_for_each(rdev1, mddev) {
+ int j = rdev1->raid_disk;
+
+ if (mddev->level == 10) {
+ /* taking over a raid10-n2 array */
+ j /= 2;
+ rdev1->new_raid_disk = j;
+ }
+
+ if (mddev->level == 1) {
+ /* taiking over a raid1 array-
+ * we have only one active disk
+ */
+ j = 0;
+ rdev1->new_raid_disk = j;
+ }
+
+ if (j < 0 || j >= mddev->raid_disks) {
+ printk(KERN_ERR "md/raid0:%s: bad disk number %d - "
+ "aborting!\n", mdname(mddev), j);
+ goto abort;
+ }
+ if (dev[j]) {
+ printk(KERN_ERR "md/raid0:%s: multiple devices for %d - "
+ "aborting!\n", mdname(mddev), j);
+ goto abort;
+ }
+ dev[j] = rdev1;
+
+ disk_stack_limits(mddev->gendisk, rdev1->bdev,
+ rdev1->data_offset << 9);
+
+ if (rdev1->bdev->bd_disk->queue->merge_bvec_fn)
+ conf->has_merge_bvec = 1;
+
+ if (!smallest || (rdev1->sectors < smallest->sectors))
+ smallest = rdev1;
+ cnt++;
+ }
+ if (cnt != mddev->raid_disks) {
+ printk(KERN_ERR "md/raid0:%s: too few disks (%d of %d) - "
+ "aborting!\n", mdname(mddev), cnt, mddev->raid_disks);
+ goto abort;
+ }
+ zone->nb_dev = cnt;
+ zone->zone_end = smallest->sectors * cnt;
+
+ curr_zone_end = zone->zone_end;
+
+ /* now do the other zones */
+ for (i = 1; i < conf->nr_strip_zones; i++)
+ {
+ int j;
+
+ zone = conf->strip_zone + i;
+ dev = conf->devlist + i * mddev->raid_disks;
+
+ pr_debug("md/raid0:%s: zone %d\n", mdname(mddev), i);
+ zone->dev_start = smallest->sectors;
+ smallest = NULL;
+ c = 0;
+
+ for (j=0; j<cnt; j++) {
+ rdev = conf->devlist[j];
+ if (rdev->sectors <= zone->dev_start) {
+ pr_debug("md/raid0:%s: checking %s ... nope\n",
+ mdname(mddev),
+ bdevname(rdev->bdev, b));
+ continue;
+ }
+ pr_debug("md/raid0:%s: checking %s ..."
+ " contained as device %d\n",
+ mdname(mddev),
+ bdevname(rdev->bdev, b), c);
+ dev[c] = rdev;
+ c++;
+ if (!smallest || rdev->sectors < smallest->sectors) {
+ smallest = rdev;
+ pr_debug("md/raid0:%s: (%llu) is smallest!.\n",
+ mdname(mddev),
+ (unsigned long long)rdev->sectors);
+ }
+ }
+
+ zone->nb_dev = c;
+ sectors = (smallest->sectors - zone->dev_start) * c;
+ pr_debug("md/raid0:%s: zone->nb_dev: %d, sectors: %llu\n",
+ mdname(mddev),
+ zone->nb_dev, (unsigned long long)sectors);
+
+ curr_zone_end += sectors;
+ zone->zone_end = curr_zone_end;
+
+ pr_debug("md/raid0:%s: current zone start: %llu\n",
+ mdname(mddev),
+ (unsigned long long)smallest->sectors);
+ }
+ mddev->queue->backing_dev_info.congested_fn = raid0_congested;
+ mddev->queue->backing_dev_info.congested_data = mddev;
+
+ /*
+ * now since we have the hard sector sizes, we can make sure
+ * chunk size is a multiple of that sector size
+ */
+ if ((mddev->chunk_sectors << 9) % queue_logical_block_size(mddev->queue)) {
+ printk(KERN_ERR "md/raid0:%s: chunk_size of %d not valid\n",
+ mdname(mddev),
+ mddev->chunk_sectors << 9);
+ goto abort;
+ }
+
+ blk_queue_io_min(mddev->queue, mddev->chunk_sectors << 9);
+ blk_queue_io_opt(mddev->queue,
+ (mddev->chunk_sectors << 9) * mddev->raid_disks);
+
+ pr_debug("md/raid0:%s: done.\n", mdname(mddev));
+ *private_conf = conf;
+
+ return 0;
+abort:
+ kfree(conf->strip_zone);
+ kfree(conf->devlist);
+ kfree(conf);
+ *private_conf = ERR_PTR(err);
+ return err;
+}
+
+/* Find the zone which holds a particular offset
+ * Update *sectorp to be an offset in that zone
+ */
+static struct strip_zone *find_zone(struct r0conf *conf,
+ sector_t *sectorp)
+{
+ int i;
+ struct strip_zone *z = conf->strip_zone;
+ sector_t sector = *sectorp;
+
+ for (i = 0; i < conf->nr_strip_zones; i++)
+ if (sector < z[i].zone_end) {
+ if (i)
+ *sectorp = sector - z[i-1].zone_end;
+ return z + i;
+ }
+ BUG();
+}
+
+/*
+ * remaps the bio to the target device. we separate two flows.
+ * power 2 flow and a general flow for the sake of perfromance
+*/
+static struct md_rdev *map_sector(struct mddev *mddev, struct strip_zone *zone,
+ sector_t sector, sector_t *sector_offset)
+{
+ unsigned int sect_in_chunk;
+ sector_t chunk;
+ struct r0conf *conf = mddev->private;
+ int raid_disks = conf->strip_zone[0].nb_dev;
+ unsigned int chunk_sects = mddev->chunk_sectors;
+
+ if (is_power_of_2(chunk_sects)) {
+ int chunksect_bits = ffz(~chunk_sects);
+ /* find the sector offset inside the chunk */
+ sect_in_chunk = sector & (chunk_sects - 1);
+ sector >>= chunksect_bits;
+ /* chunk in zone */
+ chunk = *sector_offset;
+ /* quotient is the chunk in real device*/
+ sector_div(chunk, zone->nb_dev << chunksect_bits);
+ } else{
+ sect_in_chunk = sector_div(sector, chunk_sects);
+ chunk = *sector_offset;
+ sector_div(chunk, chunk_sects * zone->nb_dev);
+ }
+ /*
+ * position the bio over the real device
+ * real sector = chunk in device + starting of zone
+ * + the position in the chunk
+ */
+ *sector_offset = (chunk * chunk_sects) + sect_in_chunk;
+ return conf->devlist[(zone - conf->strip_zone)*raid_disks
+ + sector_div(sector, zone->nb_dev)];
+}
+
+/**
+ * raid0_mergeable_bvec -- tell bio layer if two requests can be merged
+ * @q: request queue
+ * @bvm: properties of new bio
+ * @biovec: the request that could be merged to it.
+ *
+ * Return amount of bytes we can accept at this offset
+ */
+static int raid0_mergeable_bvec(struct request_queue *q,
+ struct bvec_merge_data *bvm,
+ struct bio_vec *biovec)
+{
+ struct mddev *mddev = q->queuedata;
+ struct r0conf *conf = mddev->private;
+ sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
+ sector_t sector_offset = sector;
+ int max;
+ unsigned int chunk_sectors = mddev->chunk_sectors;
+ unsigned int bio_sectors = bvm->bi_size >> 9;
+ struct strip_zone *zone;
+ struct md_rdev *rdev;
+ struct request_queue *subq;
+
+ if (is_power_of_2(chunk_sectors))
+ max = (chunk_sectors - ((sector & (chunk_sectors-1))
+ + bio_sectors)) << 9;
+ else
+ max = (chunk_sectors - (sector_div(sector, chunk_sectors)
+ + bio_sectors)) << 9;
+ if (max < 0)
+ max = 0; /* bio_add cannot handle a negative return */
+ if (max <= biovec->bv_len && bio_sectors == 0)
+ return biovec->bv_len;
+ if (max < biovec->bv_len)
+ /* too small already, no need to check further */
+ return max;
+ if (!conf->has_merge_bvec)
+ return max;
+
+ /* May need to check subordinate device */
+ sector = sector_offset;
+ zone = find_zone(mddev->private, §or_offset);
+ rdev = map_sector(mddev, zone, sector, §or_offset);
+ subq = bdev_get_queue(rdev->bdev);
+ if (subq->merge_bvec_fn) {
+ bvm->bi_bdev = rdev->bdev;
+ bvm->bi_sector = sector_offset + zone->dev_start +
+ rdev->data_offset;
+ return min(max, subq->merge_bvec_fn(subq, bvm, biovec));
+ } else
+ return max;
+}
+
+static sector_t raid0_size(struct mddev *mddev, sector_t sectors, int raid_disks)
+{
+ sector_t array_sectors = 0;
+ struct md_rdev *rdev;
+
+ WARN_ONCE(sectors || raid_disks,
+ "%s does not support generic reshape\n", __func__);
+
+ rdev_for_each(rdev, mddev)
+ array_sectors += (rdev->sectors &
+ ~(sector_t)(mddev->chunk_sectors-1));
+
+ return array_sectors;
+}
+
+static int raid0_stop(struct mddev *mddev);
+
+static int raid0_run(struct mddev *mddev)
+{
+ struct r0conf *conf;
+ int ret;
+
+ if (mddev->chunk_sectors == 0) {
+ printk(KERN_ERR "md/raid0:%s: chunk size must be set.\n",
+ mdname(mddev));
+ return -EINVAL;
+ }
+ if (md_check_no_bitmap(mddev))
+ return -EINVAL;
+ blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors);
+
+ /* if private is not null, we are here after takeover */
+ if (mddev->private == NULL) {
+ ret = create_strip_zones(mddev, &conf);
+ if (ret < 0)
+ return ret;
+ mddev->private = conf;
+ }
+ conf = mddev->private;
+
+ /* calculate array device size */
+ md_set_array_sectors(mddev, raid0_size(mddev, 0, 0));
+
+ printk(KERN_INFO "md/raid0:%s: md_size is %llu sectors.\n",
+ mdname(mddev),
+ (unsigned long long)mddev->array_sectors);
+ /* calculate the max read-ahead size.
+ * For read-ahead of large files to be effective, we need to
+ * readahead at least twice a whole stripe. i.e. number of devices
+ * multiplied by chunk size times 2.
+ * If an individual device has an ra_pages greater than the
+ * chunk size, then we will not drive that device as hard as it
+ * wants. We consider this a configuration error: a larger
+ * chunksize should be used in that case.
+ */
+ {
+ int stripe = mddev->raid_disks *
+ (mddev->chunk_sectors << 9) / PAGE_SIZE;
+ if (mddev->queue->backing_dev_info.ra_pages < 2* stripe)
+ mddev->queue->backing_dev_info.ra_pages = 2* stripe;
+ }
+
+ blk_queue_merge_bvec(mddev->queue, raid0_mergeable_bvec);
+ dump_zones(mddev);
+
+ ret = md_integrity_register(mddev);
+ if (ret)
+ raid0_stop(mddev);
+
+ return ret;
+}
+
+static int raid0_stop(struct mddev *mddev)
+{
+ struct r0conf *conf = mddev->private;
+
+ blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
+ kfree(conf->strip_zone);
+ kfree(conf->devlist);
+ kfree(conf);
+ mddev->private = NULL;
+ return 0;
+}
+
+/*
+ * Is io distribute over 1 or more chunks ?
+*/
+static inline int is_io_in_chunk_boundary(struct mddev *mddev,
+ unsigned int chunk_sects, struct bio *bio)
+{
+ if (likely(is_power_of_2(chunk_sects))) {
+ return chunk_sects >= ((bio->bi_sector & (chunk_sects-1))
+ + (bio->bi_size >> 9));
+ } else{
+ sector_t sector = bio->bi_sector;
+ return chunk_sects >= (sector_div(sector, chunk_sects)
+ + (bio->bi_size >> 9));
+ }
+}
+
+static void raid0_make_request(struct mddev *mddev, struct bio *bio)
+{
+ unsigned int chunk_sects;
+ sector_t sector_offset;
+ struct strip_zone *zone;
+ struct md_rdev *tmp_dev;
+
+ if (unlikely(bio->bi_rw & REQ_FLUSH)) {
+ md_flush_request(mddev, bio);
+ return;
+ }
+
+ chunk_sects = mddev->chunk_sectors;
+ if (unlikely(!is_io_in_chunk_boundary(mddev, chunk_sects, bio))) {
+ sector_t sector = bio->bi_sector;
+ struct bio_pair *bp;
+ /* Sanity check -- queue functions should prevent this happening */
+ if (bio->bi_vcnt != 1 ||
+ bio->bi_idx != 0)
+ goto bad_map;
+ /* This is a one page bio that upper layers
+ * refuse to split for us, so we need to split it.
+ */
+ if (likely(is_power_of_2(chunk_sects)))
+ bp = bio_split(bio, chunk_sects - (sector &
+ (chunk_sects-1)));
+ else
+ bp = bio_split(bio, chunk_sects -
+ sector_div(sector, chunk_sects));
+ raid0_make_request(mddev, &bp->bio1);
+ raid0_make_request(mddev, &bp->bio2);
+ bio_pair_release(bp);
+ return;
+ }
+
+ sector_offset = bio->bi_sector;
+ zone = find_zone(mddev->private, §or_offset);
+ tmp_dev = map_sector(mddev, zone, bio->bi_sector,
+ §or_offset);
+ bio->bi_bdev = tmp_dev->bdev;
+ bio->bi_sector = sector_offset + zone->dev_start +
+ tmp_dev->data_offset;
+
+ generic_make_request(bio);
+ return;
+
+bad_map:
+ printk("md/raid0:%s: make_request bug: can't convert block across chunks"
+ " or bigger than %dk %llu %d\n",
+ mdname(mddev), chunk_sects / 2,
+ (unsigned long long)bio->bi_sector, bio->bi_size >> 10);
+
+ bio_io_error(bio);
+ return;
+}
+
+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) {
+ printk(KERN_ERR "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) {
+ printk(KERN_ERR "md/raid0:%s: raid5 must have missing parity disk!\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->raid_disks--;
+ mddev->delta_disks = -1;
+ /* make sure it will be not marked as dirty */
+ mddev->recovery_cp = MaxSector;
+
+ 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)) {
+ printk(KERN_ERR "md/raid0:%s:: Raid0 cannot takover layout: 0x%x\n",
+ mdname(mddev),
+ mddev->layout);
+ return ERR_PTR(-EINVAL);
+ }
+ if (mddev->raid_disks & 1) {
+ printk(KERN_ERR "md/raid0:%s: Raid0 cannot takover Raid10 with odd disk number.\n",
+ mdname(mddev));
+ return ERR_PTR(-EINVAL);
+ }
+ if (mddev->degraded != (mddev->raid_disks>>1)) {
+ printk(KERN_ERR "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;
+
+ 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) {
+ printk(KERN_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;
+
+ 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->level == 4)
+ return raid0_takeover_raid45(mddev);
+
+ if (mddev->level == 5) {
+ if (mddev->layout == ALGORITHM_PARITY_N)
+ return raid0_takeover_raid45(mddev);
+
+ printk(KERN_ERR "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);
+
+ printk(KERN_ERR "Takeover from raid%i to raid0 not supported\n",
+ mddev->level);
+
+ return ERR_PTR(-EINVAL);
+}
+
+static void raid0_quiesce(struct mddev *mddev, int state)
+{
+}
+
+static struct md_personality raid0_personality=
+{
+ .name = "raid0",
+ .level = 0,
+ .owner = THIS_MODULE,
+ .make_request = raid0_make_request,
+ .run = raid0_run,
+ .stop = raid0_stop,
+ .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");