#include <linux/blkdev.h>
#include <linux/seq_file.h>
+#include <linux/slab.h>
#include "md.h"
#include "raid0.h"
static void raid0_unplug(struct request_queue *q)
{
mddev_t *mddev = q->queuedata;
- raid0_conf_t *conf = mddev_to_conf(mddev);
- mdk_rdev_t **devlist = conf->strip_zone[0].dev;
+ raid0_conf_t *conf = mddev->private;
+ mdk_rdev_t **devlist = conf->devlist;
int i;
for (i=0; i<mddev->raid_disks; i++) {
static int raid0_congested(void *data, int bits)
{
mddev_t *mddev = data;
- raid0_conf_t *conf = mddev_to_conf(mddev);
- mdk_rdev_t **devlist = conf->strip_zone[0].dev;
+ raid0_conf_t *conf = mddev->private;
+ mdk_rdev_t **devlist = conf->devlist;
int i, ret = 0;
+ if (mddev_congested(mddev, bits))
+ return 1;
+
for (i = 0; i < mddev->raid_disks && !ret ; i++) {
struct request_queue *q = bdev_get_queue(devlist[i]->bdev);
return ret;
}
-static int create_strip_zones (mddev_t *mddev)
+/*
+ * inform the user of the raid configuration
+*/
+static void dump_zones(mddev_t *mddev)
+{
+ int j, k, h;
+ sector_t zone_size = 0;
+ sector_t zone_start = 0;
+ char b[BDEVNAME_SIZE];
+ raid0_conf_t *conf = mddev->private;
+ printk(KERN_INFO "******* %s configuration *********\n",
+ mdname(mddev));
+ h = 0;
+ for (j = 0; j < conf->nr_strip_zones; j++) {
+ printk(KERN_INFO "zone%d=[", j);
+ for (k = 0; k < conf->strip_zone[j].nb_dev; k++)
+ printk("%s/",
+ bdevname(conf->devlist[j*mddev->raid_disks
+ + k]->bdev, b));
+ printk("]\n");
+
+ zone_size = conf->strip_zone[j].zone_end - zone_start;
+ printk(KERN_INFO " zone offset=%llukb "
+ "device offset=%llukb size=%llukb\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\n");
+}
+
+static int create_strip_zones(mddev_t *mddev)
{
- int i, c, j;
- sector_t curr_zone_end;
- raid0_conf_t *conf = mddev_to_conf(mddev);
- mdk_rdev_t *smallest, *rdev1, *rdev2, *rdev;
+ int i, c, err;
+ sector_t curr_zone_end, sectors;
+ mdk_rdev_t *smallest, *rdev1, *rdev2, *rdev, **dev;
struct strip_zone *zone;
int cnt;
char b[BDEVNAME_SIZE];
-
- /*
- * The number of 'same size groups'
- */
- conf->nr_strip_zones = 0;
-
+ raid0_conf_t *conf = kzalloc(sizeof(*conf), GFP_KERNEL);
+
+ if (!conf)
+ return -ENOMEM;
list_for_each_entry(rdev1, &mddev->disks, same_set) {
printk(KERN_INFO "raid0: looking at %s\n",
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;
+
list_for_each_entry(rdev2, &mddev->disks, same_set) {
printk(KERN_INFO "raid0: comparing %s(%llu)",
bdevname(rdev1->bdev,b),
}
}
printk(KERN_INFO "raid0: FINAL %d zones\n", conf->nr_strip_zones);
-
+ err = -ENOMEM;
conf->strip_zone = kzalloc(sizeof(struct strip_zone)*
conf->nr_strip_zones, GFP_KERNEL);
if (!conf->strip_zone)
- return 1;
+ goto abort;
conf->devlist = kzalloc(sizeof(mdk_rdev_t*)*
conf->nr_strip_zones*mddev->raid_disks,
GFP_KERNEL);
if (!conf->devlist)
- return 1;
+ 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;
- zone->dev = conf->devlist;
+ dev = conf->devlist;
+ err = -EINVAL;
list_for_each_entry(rdev1, &mddev->disks, same_set) {
int j = rdev1->raid_disk;
"aborting!\n", j);
goto abort;
}
- if (zone->dev[j]) {
+ if (dev[j]) {
printk(KERN_ERR "raid0: multiple devices for %d - "
"aborting!\n", j);
goto abort;
}
- zone->dev[j] = rdev1;
+ dev[j] = rdev1;
- blk_queue_stack_limits(mddev->queue,
- rdev1->bdev->bd_disk->queue);
+ disk_stack_limits(mddev->gendisk, rdev1->bdev,
+ rdev1->data_offset << 9);
/* as we don't honour merge_bvec_fn, we must never risk
- * violating it, so limit ->max_sector to one PAGE, as
- * a one page request is never in violation.
+ * violating it, so limit ->max_segments to 1, lying within
+ * a single page.
*/
- if (rdev1->bdev->bd_disk->queue->merge_bvec_fn &&
- queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
- blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
-
+ if (rdev1->bdev->bd_disk->queue->merge_bvec_fn) {
+ blk_queue_max_segments(mddev->queue, 1);
+ blk_queue_segment_boundary(mddev->queue,
+ PAGE_CACHE_SIZE - 1);
+ }
if (!smallest || (rdev1->sectors < smallest->sectors))
smallest = rdev1;
cnt++;
goto abort;
}
zone->nb_dev = cnt;
- zone->sectors = smallest->sectors * cnt;
- zone->zone_end = zone->sectors;
+ zone->zone_end = smallest->sectors * cnt;
- curr_zone_end = zone->sectors;
+ 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;
- zone->dev = conf->strip_zone[i-1].dev + mddev->raid_disks;
+ dev = conf->devlist + i * mddev->raid_disks;
printk(KERN_INFO "raid0: zone %d\n", i);
zone->dev_start = smallest->sectors;
c = 0;
for (j=0; j<cnt; j++) {
- char b[BDEVNAME_SIZE];
- rdev = conf->strip_zone[0].dev[j];
+ rdev = conf->devlist[j];
printk(KERN_INFO "raid0: checking %s ...",
bdevname(rdev->bdev, b));
if (rdev->sectors <= zone->dev_start) {
continue;
}
printk(KERN_INFO " contained as device %d\n", c);
- zone->dev[c] = rdev;
+ dev[c] = rdev;
c++;
if (!smallest || rdev->sectors < smallest->sectors) {
smallest = rdev;
}
zone->nb_dev = c;
- zone->sectors = (smallest->sectors - zone->dev_start) * c;
+ sectors = (smallest->sectors - zone->dev_start) * c;
printk(KERN_INFO "raid0: zone->nb_dev: %d, sectors: %llu\n",
- zone->nb_dev, (unsigned long long)zone->sectors);
+ zone->nb_dev, (unsigned long long)sectors);
- curr_zone_end += zone->sectors;
+ curr_zone_end += sectors;
zone->zone_end = curr_zone_end;
printk(KERN_INFO "raid0: current zone start: %llu\n",
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 "%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);
+
printk(KERN_INFO "raid0: done.\n");
+ mddev->private = conf;
return 0;
- abort:
- return 1;
+abort:
+ kfree(conf->strip_zone);
+ kfree(conf->devlist);
+ kfree(conf);
+ mddev->private = NULL;
+ return err;
}
/**
mddev_t *mddev = q->queuedata;
sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev);
int max;
- unsigned int chunk_sectors = mddev->chunk_size >> 9;
+ unsigned int chunk_sectors = mddev->chunk_sectors;
unsigned int bio_sectors = bvm->bi_size >> 9;
- max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9;
+ 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;
static int raid0_run(mddev_t *mddev)
{
- raid0_conf_t *conf;
+ int ret;
- if (mddev->chunk_size == 0) {
- printk(KERN_ERR "md/raid0: non-zero chunk size required.\n");
+ if (mddev->chunk_sectors == 0) {
+ printk(KERN_ERR "md/raid0: chunk size must be set.\n");
return -EINVAL;
}
- printk(KERN_INFO "%s: setting max_sectors to %d, segment boundary to %d\n",
- mdname(mddev),
- mddev->chunk_size >> 9,
- (mddev->chunk_size>>1)-1);
- blk_queue_max_sectors(mddev->queue, mddev->chunk_size >> 9);
- blk_queue_segment_boundary(mddev->queue, (mddev->chunk_size>>1) - 1);
+ if (md_check_no_bitmap(mddev))
+ return -EINVAL;
+ blk_queue_max_hw_sectors(mddev->queue, mddev->chunk_sectors);
mddev->queue->queue_lock = &mddev->queue->__queue_lock;
- conf = kmalloc(sizeof (raid0_conf_t), GFP_KERNEL);
- if (!conf)
- goto out;
- mddev->private = (void *)conf;
-
- conf->strip_zone = NULL;
- conf->devlist = NULL;
- if (create_strip_zones (mddev))
- goto out_free_conf;
+ ret = create_strip_zones(mddev);
+ if (ret < 0)
+ return ret;
/* calculate array device size */
md_set_array_sectors(mddev, raid0_size(mddev, 0, 0));
* chunksize should be used in that case.
*/
{
- int stripe = mddev->raid_disks * mddev->chunk_size / PAGE_SIZE;
+ 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);
+ md_integrity_register(mddev);
return 0;
-
-out_free_conf:
- kfree(conf->strip_zone);
- kfree(conf->devlist);
- kfree(conf);
- mddev->private = NULL;
-out:
- return -ENOMEM;
}
-static int raid0_stop (mddev_t *mddev)
+static int raid0_stop(mddev_t *mddev)
{
- raid0_conf_t *conf = mddev_to_conf(mddev);
+ raid0_conf_t *conf = mddev->private;
blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
kfree(conf->strip_zone);
- conf->strip_zone = NULL;
+ kfree(conf->devlist);
kfree(conf);
mddev->private = NULL;
-
return 0;
}
-/* Find the zone which holds a particular offset */
+/* Find the zone which holds a particular offset
+ * Update *sectorp to be an offset in that zone
+ */
static struct strip_zone *find_zone(struct raid0_private_data *conf,
- sector_t sector)
+ 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 (sector < z[i].zone_end) {
+ if (i)
+ *sectorp = sector - z[i-1].zone_end;
return z + i;
+ }
BUG();
}
-static int raid0_make_request (struct request_queue *q, struct bio *bio)
+/*
+ * remaps the bio to the target device. we separate two flows.
+ * power 2 flow and a general flow for the sake of perfromance
+*/
+static mdk_rdev_t *map_sector(mddev_t *mddev, struct strip_zone *zone,
+ sector_t sector, sector_t *sector_offset)
+{
+ unsigned int sect_in_chunk;
+ sector_t chunk;
+ raid0_conf_t *conf = mddev->private;
+ 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)*mddev->raid_disks
+ + sector_div(sector, zone->nb_dev)];
+}
+
+/*
+ * Is io distribute over 1 or more chunks ?
+*/
+static inline int is_io_in_chunk_boundary(mddev_t *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 int raid0_make_request(struct request_queue *q, struct bio *bio)
{
mddev_t *mddev = q->queuedata;
- unsigned int sect_in_chunk, chunksect_bits, chunk_sects;
- raid0_conf_t *conf = mddev_to_conf(mddev);
+ unsigned int chunk_sects;
+ sector_t sector_offset;
struct strip_zone *zone;
mdk_rdev_t *tmp_dev;
- sector_t chunk;
- sector_t sector, rsect;
const int rw = bio_data_dir(bio);
int cpu;
- if (unlikely(bio_barrier(bio))) {
- bio_endio(bio, -EOPNOTSUPP);
+ if (unlikely(bio_rw_flagged(bio, BIO_RW_BARRIER))) {
+ md_barrier_request(mddev, bio);
return 0;
}
bio_sectors(bio));
part_stat_unlock();
- chunk_sects = mddev->chunk_size >> 9;
- chunksect_bits = ffz(~chunk_sects);
- sector = bio->bi_sector;
-
- if (unlikely(chunk_sects < (bio->bi_sector & (chunk_sects - 1)) + (bio->bi_size >> 9))) {
+ 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 ||
/* This is a one page bio that upper layers
* refuse to split for us, so we need to split it.
*/
- bp = bio_split(bio, chunk_sects - (bio->bi_sector & (chunk_sects - 1)));
+ 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));
if (raid0_make_request(q, &bp->bio1))
generic_make_request(&bp->bio1);
if (raid0_make_request(q, &bp->bio2))
bio_pair_release(bp);
return 0;
}
- zone = find_zone(conf, sector);
- sect_in_chunk = bio->bi_sector & (chunk_sects - 1);
- {
- sector_t x = (zone->sectors + sector - zone->zone_end)
- >> chunksect_bits;
-
- sector_div(x, zone->nb_dev);
- chunk = x;
- x = sector >> chunksect_bits;
- tmp_dev = zone->dev[sector_div(x, zone->nb_dev)];
- }
- rsect = (chunk << chunksect_bits) + zone->dev_start + sect_in_chunk;
-
+ 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 = rsect + tmp_dev->data_offset;
-
+ bio->bi_sector = sector_offset + zone->dev_start +
+ tmp_dev->data_offset;
/*
* Let the main block layer submit the IO and resolve recursion:
*/
return 0;
}
-static void raid0_status (struct seq_file *seq, mddev_t *mddev)
+static void raid0_status(struct seq_file *seq, mddev_t *mddev)
{
#undef MD_DEBUG
#ifdef MD_DEBUG
int j, k, h;
char b[BDEVNAME_SIZE];
- raid0_conf_t *conf = mddev_to_conf(mddev);
+ raid0_conf_t *conf = mddev->private;
+ sector_t zone_size;
+ sector_t zone_start = 0;
h = 0;
+
for (j = 0; j < conf->nr_strip_zones; j++) {
seq_printf(seq, " z%d", j);
seq_printf(seq, "=[");
for (k = 0; k < conf->strip_zone[j].nb_dev; k++)
seq_printf(seq, "%s/", bdevname(
- conf->strip_zone[j].dev[k]->bdev,b));
-
- seq_printf(seq, "] ze=%d ds=%d s=%d\n",
- conf->strip_zone[j].zone_end,
- conf->strip_zone[j].dev_start,
- conf->strip_zone[j].sectors);
+ conf->devlist[j*mddev->raid_disks + k]
+ ->bdev, b));
+
+ zone_size = conf->strip_zone[j].zone_end - zone_start;
+ seq_printf(seq, "] ze=%lld ds=%lld s=%lld\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;
}
#endif
- seq_printf(seq, " %dk chunks", mddev->chunk_size/1024);
+ seq_printf(seq, " %dk chunks", mddev->chunk_sectors / 2);
return;
}
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");