raid10 Various RAID10 inspired algorithms chosen by additional params
- RAID10: Striped Mirrors (aka 'Striping on top of mirrors')
- RAID1E: Integrated Adjacent Stripe Mirroring
+ - RAID1E: Integrated Offset Stripe Mirroring
- and other similar RAID10 variants
Reference: Chapter 4 of
synchronisation state for each region.
[raid10_copies <# copies>]
- [raid10_format near]
+ [raid10_format <near|far|offset>]
These two options are used to alter the default layout of
a RAID10 configuration. The number of copies is can be
- specified, but the default is 2. There are other variations
- to how the copies are laid down - the default and only current
- option is "near". Near copies are what most people think of
- with respect to mirroring. If these options are left
- unspecified, or 'raid10_copies 2' and/or 'raid10_format near'
- are given, then the layouts for 2, 3 and 4 devices are:
+ specified, but the default is 2. There are also three
+ variations to how the copies are laid down - the default
+ is "near". Near copies are what most people think of with
+ respect to mirroring. If these options are left unspecified,
+ or 'raid10_copies 2' and/or 'raid10_format near' are given,
+ then the layouts for 2, 3 and 4 devices are:
2 drives 3 drives 4 drives
-------- ---------- --------------
A1 A1 A1 A1 A2 A1 A1 A2 A2
3-device layout is what might be called a 'RAID1E - Integrated
Adjacent Stripe Mirroring'.
+ If 'raid10_copies 2' and 'raid10_format far', then the layouts
+ for 2, 3 and 4 devices are:
+ 2 drives 3 drives 4 drives
+ -------- -------------- --------------------
+ A1 A2 A1 A2 A3 A1 A2 A3 A4
+ A3 A4 A4 A5 A6 A5 A6 A7 A8
+ A5 A6 A7 A8 A9 A9 A10 A11 A12
+ .. .. .. .. .. .. .. .. ..
+ A2 A1 A3 A1 A2 A2 A1 A4 A3
+ A4 A3 A6 A4 A5 A6 A5 A8 A7
+ A6 A5 A9 A7 A8 A10 A9 A12 A11
+ .. .. .. .. .. .. .. .. ..
+
+ If 'raid10_copies 2' and 'raid10_format offset', then the
+ layouts for 2, 3 and 4 devices are:
+ 2 drives 3 drives 4 drives
+ -------- ------------ -----------------
+ A1 A2 A1 A2 A3 A1 A2 A3 A4
+ A2 A1 A3 A1 A2 A2 A1 A4 A3
+ A3 A4 A4 A5 A6 A5 A6 A7 A8
+ A4 A3 A6 A4 A5 A6 A5 A8 A7
+ A5 A6 A7 A8 A9 A9 A10 A11 A12
+ A6 A5 A9 A7 A8 A10 A9 A12 A11
+ .. .. .. .. .. .. .. .. ..
+ Here we see layouts closely akin to 'RAID1E - Integrated
+ Offset Stripe Mirroring'.
+
<#raid_devs>: The number of devices composing the array.
Each device consists of two entries. The first is the device
containing the metadata (if any); the second is the one containing the
1.3.0 Added support for RAID 10
1.3.1 Allow device replacement/rebuild for RAID 10
1.3.2 Fix/improve redundancy checking for RAID10
+1.4.0 Non-functional change. Removes arg from mapping function.
+1.4.1 Add RAID10 "far" and "offset" algorithm support.
If unsure, say Y.
-config MULTICORE_RAID456
- bool "RAID-4/RAID-5/RAID-6 Multicore processing (EXPERIMENTAL)"
- depends on MD_RAID456
- depends on SMP
- depends on EXPERIMENTAL
- ---help---
- Enable the raid456 module to dispatch per-stripe raid operations to a
- thread pool.
-
- If unsure, say N.
-
config MD_MULTIPATH
tristate "Multipath I/O support"
depends on BLK_DEV_MD
{"raid6_nc", "RAID6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE}
};
+static char *raid10_md_layout_to_format(int layout)
+{
+ /*
+ * Bit 16 and 17 stand for "offset" and "use_far_sets"
+ * Refer to MD's raid10.c for details
+ */
+ if ((layout & 0x10000) && (layout & 0x20000))
+ return "offset";
+
+ if ((layout & 0xFF) > 1)
+ return "near";
+
+ return "far";
+}
+
static unsigned raid10_md_layout_to_copies(int layout)
{
- return layout & 0xFF;
+ if ((layout & 0xFF) > 1)
+ return layout & 0xFF;
+ return (layout >> 8) & 0xFF;
}
static int raid10_format_to_md_layout(char *format, unsigned copies)
{
- /* 1 "far" copy, and 'copies' "near" copies */
- return (1 << 8) | (copies & 0xFF);
+ unsigned n = 1, f = 1;
+
+ if (!strcmp("near", format))
+ n = copies;
+ else
+ f = copies;
+
+ if (!strcmp("offset", format))
+ return 0x30000 | (f << 8) | n;
+
+ if (!strcmp("far", format))
+ return 0x20000 | (f << 8) | n;
+
+ return (f << 8) | n;
}
static struct raid_type *get_raid_type(char *name)
{
unsigned i, rebuild_cnt = 0;
unsigned rebuilds_per_group, copies, d;
+ unsigned group_size, last_group_start;
for (i = 0; i < rs->md.raid_disks; i++)
if (!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
* as long as the failed devices occur in different mirror
* groups (i.e. different stripes).
*
- * Right now, we only allow for "near" copies. When other
- * formats are added, we will have to check those too.
- *
* When checking "near" format, make sure no adjacent devices
* have failed beyond what can be handled. In addition to the
* simple case where the number of devices is a multiple of the
* A A B B C
* C D D E E
*/
- for (i = 0; i < rs->md.raid_disks * copies; i++) {
- if (!(i % copies))
+ if (!strcmp("near", raid10_md_layout_to_format(rs->md.layout))) {
+ for (i = 0; i < rs->md.raid_disks * copies; i++) {
+ if (!(i % copies))
+ rebuilds_per_group = 0;
+ d = i % rs->md.raid_disks;
+ if ((!rs->dev[d].rdev.sb_page ||
+ !test_bit(In_sync, &rs->dev[d].rdev.flags)) &&
+ (++rebuilds_per_group >= copies))
+ goto too_many;
+ }
+ break;
+ }
+
+ /*
+ * When checking "far" and "offset" formats, we need to ensure
+ * that the device that holds its copy is not also dead or
+ * being rebuilt. (Note that "far" and "offset" formats only
+ * support two copies right now. These formats also only ever
+ * use the 'use_far_sets' variant.)
+ *
+ * This check is somewhat complicated by the need to account
+ * for arrays that are not a multiple of (far) copies. This
+ * results in the need to treat the last (potentially larger)
+ * set differently.
+ */
+ group_size = (rs->md.raid_disks / copies);
+ last_group_start = (rs->md.raid_disks / group_size) - 1;
+ last_group_start *= group_size;
+ for (i = 0; i < rs->md.raid_disks; i++) {
+ if (!(i % copies) && !(i > last_group_start))
rebuilds_per_group = 0;
- d = i % rs->md.raid_disks;
- if ((!rs->dev[d].rdev.sb_page ||
- !test_bit(In_sync, &rs->dev[d].rdev.flags)) &&
+ if ((!rs->dev[i].rdev.sb_page ||
+ !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
(++rebuilds_per_group >= copies))
- goto too_many;
+ goto too_many;
}
break;
default:
*
* RAID10-only options:
* [raid10_copies <# copies>] Number of copies. (Default: 2)
- * [raid10_format <near>] Layout algorithm. (Default: near)
+ * [raid10_format <near|far|offset>] Layout algorithm. (Default: near)
*/
static int parse_raid_params(struct raid_set *rs, char **argv,
unsigned num_raid_params)
rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
return -EINVAL;
}
- if (strcmp("near", argv[i])) {
+ if (strcmp("near", argv[i]) &&
+ strcmp("far", argv[i]) &&
+ strcmp("offset", argv[i])) {
rs->ti->error = "Invalid 'raid10_format' value given";
return -EINVAL;
}
return -EINVAL;
}
+ /*
+ * If the format is not "near", we only support
+ * two copies at the moment.
+ */
+ if (strcmp("near", raid10_format) && (raid10_copies > 2)) {
+ rs->ti->error = "Too many copies for given RAID10 format.";
+ return -EINVAL;
+ }
+
/* (Len * #mirrors) / #devices */
sectors_per_dev = rs->ti->len * raid10_copies;
sector_div(sectors_per_dev, rs->md.raid_disks);
/*
* Reshaping is not currently allowed
*/
- if ((le32_to_cpu(sb->level) != mddev->level) ||
- (le32_to_cpu(sb->layout) != mddev->layout) ||
- (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors)) {
- DMERR("Reshaping arrays not yet supported.");
+ if (le32_to_cpu(sb->level) != mddev->level) {
+ DMERR("Reshaping arrays not yet supported. (RAID level change)");
+ return -EINVAL;
+ }
+ if (le32_to_cpu(sb->layout) != mddev->layout) {
+ DMERR("Reshaping arrays not yet supported. (RAID layout change)");
+ DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb->layout), mddev->layout);
+ DMERR(" Old layout: %s w/ %d copies",
+ raid10_md_layout_to_format(le32_to_cpu(sb->layout)),
+ raid10_md_layout_to_copies(le32_to_cpu(sb->layout)));
+ DMERR(" New layout: %s w/ %d copies",
+ raid10_md_layout_to_format(mddev->layout),
+ raid10_md_layout_to_copies(mddev->layout));
+ return -EINVAL;
+ }
+ if (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors) {
+ DMERR("Reshaping arrays not yet supported. (stripe sectors change)");
return -EINVAL;
}
/* We can only change the number of devices in RAID1 right now */
if ((rs->raid_type->level != 1) &&
(le32_to_cpu(sb->num_devices) != mddev->raid_disks)) {
- DMERR("Reshaping arrays not yet supported.");
+ DMERR("Reshaping arrays not yet supported. (device count change)");
return -EINVAL;
}
raid10_md_layout_to_copies(rs->md.layout));
if (rs->print_flags & DMPF_RAID10_FORMAT)
- DMEMIT(" raid10_format near");
+ DMEMIT(" raid10_format %s",
+ raid10_md_layout_to_format(rs->md.layout));
DMEMIT(" %d", rs->md.raid_disks);
for (i = 0; i < rs->md.raid_disks; i++) {
static int __init dm_raid_init(void)
{
+ DMINFO("Loading target version %u.%u.%u",
+ raid_target.version[0],
+ raid_target.version[1],
+ raid_target.version[2]);
return dm_register_target(&raid_target);
}
bio_io_error(bio);
return;
}
+ if (mddev->ro == 1 && unlikely(rw == WRITE)) {
+ bio_endio(bio, bio_sectors(bio) == 0 ? 0 : -EROFS);
+ return;
+ }
smp_rmb(); /* Ensure implications of 'active' are visible */
rcu_read_lock();
if (mddev->suspended) {
} else if (!sectors)
sectors = (i_size_read(rdev->bdev->bd_inode) >> 9) -
rdev->data_offset;
+ if (!my_mddev->pers->resize)
+ /* Cannot change size for RAID0 or Linear etc */
+ return -EINVAL;
}
if (sectors < my_mddev->dev_sectors)
return -EINVAL; /* component must fit device */
mddev->ro = 0;
sysfs_notify_dirent_safe(mddev->sysfs_state);
set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
- md_wakeup_thread(mddev->thread);
+ /* mddev_unlock will wake thread */
+ /* If a device failed while we were read-only, we
+ * need to make sure the metadata is updated now.
+ */
+ if (test_bit(MD_CHANGE_DEVS, &mddev->flags)) {
+ mddev_unlock(mddev);
+ wait_event(mddev->sb_wait,
+ !test_bit(MD_CHANGE_DEVS, &mddev->flags) &&
+ !test_bit(MD_CHANGE_PENDING, &mddev->flags));
+ mddev_lock(mddev);
+ }
} else {
err = -EROFS;
goto abort_unlock;
rdev1->new_raid_disk = j;
}
- if (j < 0 || j >= mddev->raid_disks) {
+ if (j < 0) {
+ printk(KERN_ERR
+ "md/raid0:%s: remove inactive devices before converting to RAID0\n",
+ mdname(mddev));
+ goto abort;
+ }
+ if (j >= mddev->raid_disks) {
printk(KERN_ERR "md/raid0:%s: bad disk number %d - "
"aborting!\n", mdname(mddev), j);
goto abort;
kfree(conf->strip_zone);
kfree(conf->devlist);
kfree(conf);
- *private_conf = NULL;
+ *private_conf = ERR_PTR(err);
return err;
}
"%s does not support generic reshape\n", __func__);
rdev_for_each(rdev, mddev)
- array_sectors += rdev->sectors;
+ array_sectors += (rdev->sectors &
+ ~(sector_t)(mddev->chunk_sectors-1));
return array_sectors;
}
bio_list_merge(&conf->pending_bio_list, &plug->pending);
conf->pending_count += plug->pending_cnt;
spin_unlock_irq(&conf->device_lock);
+ wake_up(&conf->wait_barrier);
md_wakeup_thread(mddev->thread);
kfree(plug);
return;
const unsigned long do_flush_fua = (bio->bi_rw & (REQ_FLUSH | REQ_FUA));
const unsigned long do_discard = (bio->bi_rw
& (REQ_DISCARD | REQ_SECURE));
+ const unsigned long do_same = (bio->bi_rw & REQ_WRITE_SAME);
struct md_rdev *blocked_rdev;
struct blk_plug_cb *cb;
struct raid1_plug_cb *plug = NULL;
conf->mirrors[i].rdev->data_offset);
mbio->bi_bdev = conf->mirrors[i].rdev->bdev;
mbio->bi_end_io = raid1_end_write_request;
- mbio->bi_rw = WRITE | do_flush_fua | do_sync | do_discard;
+ mbio->bi_rw =
+ WRITE | do_flush_fua | do_sync | do_discard | do_same;
mbio->bi_private = r1_bio;
atomic_inc(&r1_bio->remaining);
if (IS_ERR(conf))
return PTR_ERR(conf);
+ if (mddev->queue)
+ blk_queue_max_write_same_sectors(mddev->queue,
+ mddev->chunk_sectors);
rdev_for_each(rdev, mddev) {
if (!mddev->gendisk)
continue;
* near_copies (stored in low byte of layout)
* far_copies (stored in second byte of layout)
* far_offset (stored in bit 16 of layout )
+ * use_far_sets (stored in bit 17 of layout )
*
- * The data to be stored is divided into chunks using chunksize.
- * Each device is divided into far_copies sections.
- * In each section, chunks are laid out in a style similar to raid0, but
- * near_copies copies of each chunk is stored (each on a different drive).
- * The starting device for each section is offset near_copies from the starting
- * device of the previous section.
- * Thus they are (near_copies*far_copies) of each chunk, and each is on a different
- * drive.
- * near_copies and far_copies must be at least one, and their product is at most
- * raid_disks.
+ * The data to be stored is divided into chunks using chunksize. Each device
+ * is divided into far_copies sections. In each section, chunks are laid out
+ * in a style similar to raid0, but near_copies copies of each chunk is stored
+ * (each on a different drive). The starting device for each section is offset
+ * near_copies from the starting device of the previous section. Thus there
+ * are (near_copies * far_copies) of each chunk, and each is on a different
+ * drive. near_copies and far_copies must be at least one, and their product
+ * is at most raid_disks.
*
* If far_offset is true, then the far_copies are handled a bit differently.
- * The copies are still in different stripes, but instead of be very far apart
- * on disk, there are adjacent stripes.
+ * The copies are still in different stripes, but instead of being very far
+ * apart on disk, there are adjacent stripes.
+ *
+ * The far and offset algorithms are handled slightly differently if
+ * 'use_far_sets' is true. In this case, the array's devices are grouped into
+ * sets that are (near_copies * far_copies) in size. The far copied stripes
+ * are still shifted by 'near_copies' devices, but this shifting stays confined
+ * to the set rather than the entire array. This is done to improve the number
+ * of device combinations that can fail without causing the array to fail.
+ * Example 'far' algorithm w/o 'use_far_sets' (each letter represents a chunk
+ * on a device):
+ * A B C D A B C D E
+ * ... ...
+ * D A B C E A B C D
+ * Example 'far' algorithm w/ 'use_far_sets' enabled (sets illustrated w/ []'s):
+ * [A B] [C D] [A B] [C D E]
+ * |...| |...| |...| | ... |
+ * [B A] [D C] [B A] [E C D]
*/
/*
sector_t stripe;
int dev;
int slot = 0;
+ int last_far_set_start, last_far_set_size;
+
+ last_far_set_start = (geo->raid_disks / geo->far_set_size) - 1;
+ last_far_set_start *= geo->far_set_size;
+
+ last_far_set_size = geo->far_set_size;
+ last_far_set_size += (geo->raid_disks % geo->far_set_size);
/* now calculate first sector/dev */
chunk = r10bio->sector >> geo->chunk_shift;
/* and calculate all the others */
for (n = 0; n < geo->near_copies; n++) {
int d = dev;
+ int set;
sector_t s = sector;
- r10bio->devs[slot].addr = sector;
r10bio->devs[slot].devnum = d;
+ r10bio->devs[slot].addr = s;
slot++;
for (f = 1; f < geo->far_copies; f++) {
+ set = d / geo->far_set_size;
d += geo->near_copies;
- if (d >= geo->raid_disks)
- d -= geo->raid_disks;
+
+ if ((geo->raid_disks % geo->far_set_size) &&
+ (d > last_far_set_start)) {
+ d -= last_far_set_start;
+ d %= last_far_set_size;
+ d += last_far_set_start;
+ } else {
+ d %= geo->far_set_size;
+ d += geo->far_set_size * set;
+ }
s += geo->stride;
r10bio->devs[slot].devnum = d;
r10bio->devs[slot].addr = s;
* or recovery, so reshape isn't happening
*/
struct geom *geo = &conf->geo;
+ int far_set_start = (dev / geo->far_set_size) * geo->far_set_size;
+ int far_set_size = geo->far_set_size;
+ int last_far_set_start;
+
+ if (geo->raid_disks % geo->far_set_size) {
+ last_far_set_start = (geo->raid_disks / geo->far_set_size) - 1;
+ last_far_set_start *= geo->far_set_size;
+
+ if (dev >= last_far_set_start) {
+ far_set_size = geo->far_set_size;
+ far_set_size += (geo->raid_disks % geo->far_set_size);
+ far_set_start = last_far_set_start;
+ }
+ }
offset = sector & geo->chunk_mask;
if (geo->far_offset) {
chunk = sector >> geo->chunk_shift;
fc = sector_div(chunk, geo->far_copies);
dev -= fc * geo->near_copies;
- if (dev < 0)
- dev += geo->raid_disks;
+ if (dev < far_set_start)
+ dev += far_set_size;
} else {
while (sector >= geo->stride) {
sector -= geo->stride;
- if (dev < geo->near_copies)
- dev += geo->raid_disks - geo->near_copies;
+ if (dev < (geo->near_copies + far_set_start))
+ dev += far_set_size - geo->near_copies;
else
dev -= geo->near_copies;
}
bio_list_merge(&conf->pending_bio_list, &plug->pending);
conf->pending_count += plug->pending_cnt;
spin_unlock_irq(&conf->device_lock);
+ wake_up(&conf->wait_barrier);
md_wakeup_thread(mddev->thread);
kfree(plug);
return;
const unsigned long do_fua = (bio->bi_rw & REQ_FUA);
const unsigned long do_discard = (bio->bi_rw
& (REQ_DISCARD | REQ_SECURE));
+ const unsigned long do_same = (bio->bi_rw & REQ_WRITE_SAME);
unsigned long flags;
struct md_rdev *blocked_rdev;
struct blk_plug_cb *cb;
rdev));
mbio->bi_bdev = rdev->bdev;
mbio->bi_end_io = raid10_end_write_request;
- mbio->bi_rw = WRITE | do_sync | do_fua | do_discard;
+ mbio->bi_rw =
+ WRITE | do_sync | do_fua | do_discard | do_same;
mbio->bi_private = r10_bio;
atomic_inc(&r10_bio->remaining);
r10_bio, rdev));
mbio->bi_bdev = rdev->bdev;
mbio->bi_end_io = raid10_end_write_request;
- mbio->bi_rw = WRITE | do_sync | do_fua | do_discard;
+ mbio->bi_rw =
+ WRITE | do_sync | do_fua | do_discard | do_same;
mbio->bi_private = r10_bio;
atomic_inc(&r10_bio->remaining);
disks = mddev->raid_disks + mddev->delta_disks;
break;
}
- if (layout >> 17)
+ if (layout >> 18)
return -1;
if (chunk < (PAGE_SIZE >> 9) ||
!is_power_of_2(chunk))
geo->near_copies = nc;
geo->far_copies = fc;
geo->far_offset = fo;
+ geo->far_set_size = (layout & (1<<17)) ? disks / fc : disks;
geo->chunk_mask = chunk - 1;
geo->chunk_shift = ffz(~chunk);
return nc*fc;
if (mddev->queue) {
blk_queue_max_discard_sectors(mddev->queue,
mddev->chunk_sectors);
+ blk_queue_max_write_same_sectors(mddev->queue,
+ mddev->chunk_sectors);
blk_queue_io_min(mddev->queue, chunk_size);
if (conf->geo.raid_disks % conf->geo.near_copies)
blk_queue_io_opt(mddev->queue, chunk_size * conf->geo.raid_disks);
* far_offset, in which case it is
* 1 stripe.
*/
+ int far_set_size; /* The number of devices in a set,
+ * where a 'set' are devices that
+ * contain far/offset copies of
+ * each other.
+ */
int chunk_shift; /* shift from chunks to sectors */
sector_t chunk_mask;
} prev, geo;
&sh->ops.zero_sum_result, percpu->spare_page, &submit);
}
-static void __raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
+static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
{
int overlap_clear = 0, i, disks = sh->disks;
struct dma_async_tx_descriptor *tx = NULL;
put_cpu();
}
-#ifdef CONFIG_MULTICORE_RAID456
-static void async_run_ops(void *param, async_cookie_t cookie)
-{
- struct stripe_head *sh = param;
- unsigned long ops_request = sh->ops.request;
-
- clear_bit_unlock(STRIPE_OPS_REQ_PENDING, &sh->state);
- wake_up(&sh->ops.wait_for_ops);
-
- __raid_run_ops(sh, ops_request);
- release_stripe(sh);
-}
-
-static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
-{
- /* since handle_stripe can be called outside of raid5d context
- * we need to ensure sh->ops.request is de-staged before another
- * request arrives
- */
- wait_event(sh->ops.wait_for_ops,
- !test_and_set_bit_lock(STRIPE_OPS_REQ_PENDING, &sh->state));
- sh->ops.request = ops_request;
-
- atomic_inc(&sh->count);
- async_schedule(async_run_ops, sh);
-}
-#else
-#define raid_run_ops __raid_run_ops
-#endif
-
static int grow_one_stripe(struct r5conf *conf)
{
struct stripe_head *sh;
return 0;
sh->raid_conf = conf;
- #ifdef CONFIG_MULTICORE_RAID456
- init_waitqueue_head(&sh->ops.wait_for_ops);
- #endif
spin_lock_init(&sh->stripe_lock);
break;
nsh->raid_conf = conf;
- #ifdef CONFIG_MULTICORE_RAID456
- init_waitqueue_head(&nsh->ops.wait_for_ops);
- #endif
spin_lock_init(&nsh->stripe_lock);
list_add(&nsh->lru, &newstripes);
projects / linux-drm-fsl-dcu.git / commitdiff