diff options
Diffstat (limited to 'ANDROID_3.4.5/drivers/md/raid0.c')
| -rw-r--r-- | ANDROID_3.4.5/drivers/md/raid0.c | 739 |
1 files changed, 0 insertions, 739 deletions
diff --git a/ANDROID_3.4.5/drivers/md/raid0.c b/ANDROID_3.4.5/drivers/md/raid0.c deleted file mode 100644 index de63a1fc..00000000 --- a/ANDROID_3.4.5/drivers/md/raid0.c +++ /dev/null @@ -1,739 +0,0 @@ -/* - 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 = NULL; - 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; - - 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"); |