drbd: Allow online change of al-stripes and al-stripe-size

Allow to change the AL layout with an resize operation. For that
the reisze command gets two new fields: al_stripes and al_stripe_size.

In order to make the operation crash save:
1) Lock out all IO and MD-IO
2) Write the super block with MDF_PRIMARY_IND clear
3) write the bitmap to the new location (all zeros, since
   we allow only while connected)
4) Initialize the new AL-area
5) Write the super block with the restored MDF_PRIMARY_IND.
6) Unfreeze all IO

Since the AL-layout has no influence on the protocol, this operation
needs to be beforemed on both sides of a resource (if intended).

Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Philipp Reisner 2013-06-25 16:50:08 +02:00 committed by Jens Axboe
parent e96c96333f
commit d752b26960
8 changed files with 188 additions and 53 deletions

View File

@ -659,6 +659,27 @@ void drbd_al_shrink(struct drbd_conf *mdev)
wake_up(&mdev->al_wait);
}
int drbd_initialize_al(struct drbd_conf *mdev, void *buffer)
{
struct al_transaction_on_disk *al = buffer;
struct drbd_md *md = &mdev->ldev->md;
sector_t al_base = md->md_offset + md->al_offset;
int al_size_4k = md->al_stripes * md->al_stripe_size_4k;
int i;
memset(al, 0, 4096);
al->magic = cpu_to_be32(DRBD_AL_MAGIC);
al->transaction_type = cpu_to_be16(AL_TR_INITIALIZED);
al->crc32c = cpu_to_be32(crc32c(0, al, 4096));
for (i = 0; i < al_size_4k; i++) {
int err = drbd_md_sync_page_io(mdev, mdev->ldev, al_base + i * 8, WRITE);
if (err)
return err;
}
return 0;
}
static int w_update_odbm(struct drbd_work *w, int unused)
{
struct update_odbm_work *udw = container_of(w, struct update_odbm_work, w);

View File

@ -1133,6 +1133,7 @@ extern void drbd_mdev_cleanup(struct drbd_conf *mdev);
void drbd_print_uuids(struct drbd_conf *mdev, const char *text);
extern void conn_md_sync(struct drbd_tconn *tconn);
extern void drbd_md_write(struct drbd_conf *mdev, void *buffer);
extern void drbd_md_sync(struct drbd_conf *mdev);
extern int drbd_md_read(struct drbd_conf *mdev, struct drbd_backing_dev *bdev);
extern void drbd_uuid_set(struct drbd_conf *mdev, int idx, u64 val) __must_hold(local);
@ -1468,12 +1469,15 @@ extern void drbd_resume_io(struct drbd_conf *mdev);
extern char *ppsize(char *buf, unsigned long long size);
extern sector_t drbd_new_dev_size(struct drbd_conf *, struct drbd_backing_dev *, sector_t, int);
enum determine_dev_size {
DS_ERROR_SHRINK = -3,
DS_ERROR_SPACE_MD = -2,
DS_ERROR = -1,
DS_UNCHANGED = 0,
DS_SHRUNK = 1,
DS_GREW = 2
};
extern enum determine_dev_size drbd_determine_dev_size(struct drbd_conf *, enum dds_flags) __must_hold(local);
extern enum determine_dev_size
drbd_determine_dev_size(struct drbd_conf *, enum dds_flags, struct resize_parms *) __must_hold(local);
extern void resync_after_online_grow(struct drbd_conf *);
extern void drbd_reconsider_max_bio_size(struct drbd_conf *mdev);
extern enum drbd_state_rv drbd_set_role(struct drbd_conf *mdev,
@ -1639,6 +1643,7 @@ extern int __drbd_set_out_of_sync(struct drbd_conf *mdev, sector_t sector,
#define drbd_set_out_of_sync(mdev, sector, size) \
__drbd_set_out_of_sync(mdev, sector, size, __FILE__, __LINE__)
extern void drbd_al_shrink(struct drbd_conf *mdev);
extern int drbd_initialize_al(struct drbd_conf *, void *);
/* drbd_nl.c */
/* state info broadcast */

View File

@ -2879,34 +2879,14 @@ struct meta_data_on_disk {
u8 reserved_u8[4096 - (7*8 + 10*4)];
} __packed;
/**
* drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
* @mdev: DRBD device.
*/
void drbd_md_sync(struct drbd_conf *mdev)
void drbd_md_write(struct drbd_conf *mdev, void *b)
{
struct meta_data_on_disk *buffer;
struct meta_data_on_disk *buffer = b;
sector_t sector;
int i;
/* Don't accidentally change the DRBD meta data layout. */
BUILD_BUG_ON(UI_SIZE != 4);
BUILD_BUG_ON(sizeof(struct meta_data_on_disk) != 4096);
del_timer(&mdev->md_sync_timer);
/* timer may be rearmed by drbd_md_mark_dirty() now. */
if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
return;
/* We use here D_FAILED and not D_ATTACHING because we try to write
* metadata even if we detach due to a disk failure! */
if (!get_ldev_if_state(mdev, D_FAILED))
return;
buffer = drbd_md_get_buffer(mdev);
if (!buffer)
goto out;
memset(buffer, 0, sizeof(*buffer));
buffer->la_size_sect = cpu_to_be64(drbd_get_capacity(mdev->this_bdev));
@ -2935,6 +2915,35 @@ void drbd_md_sync(struct drbd_conf *mdev)
dev_err(DEV, "meta data update failed!\n");
drbd_chk_io_error(mdev, 1, DRBD_META_IO_ERROR);
}
}
/**
* drbd_md_sync() - Writes the meta data super block if the MD_DIRTY flag bit is set
* @mdev: DRBD device.
*/
void drbd_md_sync(struct drbd_conf *mdev)
{
struct meta_data_on_disk *buffer;
/* Don't accidentally change the DRBD meta data layout. */
BUILD_BUG_ON(UI_SIZE != 4);
BUILD_BUG_ON(sizeof(struct meta_data_on_disk) != 4096);
del_timer(&mdev->md_sync_timer);
/* timer may be rearmed by drbd_md_mark_dirty() now. */
if (!test_and_clear_bit(MD_DIRTY, &mdev->flags))
return;
/* We use here D_FAILED and not D_ATTACHING because we try to write
* metadata even if we detach due to a disk failure! */
if (!get_ldev_if_state(mdev, D_FAILED))
return;
buffer = drbd_md_get_buffer(mdev);
if (!buffer)
goto out;
drbd_md_write(mdev, buffer);
/* Update mdev->ldev->md.la_size_sect,
* since we updated it on metadata. */

View File

@ -827,12 +827,17 @@ void drbd_resume_io(struct drbd_conf *mdev)
* Returns 0 on success, negative return values indicate errors.
* You should call drbd_md_sync() after calling this function.
*/
enum determine_dev_size drbd_determine_dev_size(struct drbd_conf *mdev, enum dds_flags flags) __must_hold(local)
enum determine_dev_size
drbd_determine_dev_size(struct drbd_conf *mdev, enum dds_flags flags, struct resize_parms *rs) __must_hold(local)
{
sector_t prev_first_sect, prev_size; /* previous meta location */
sector_t la_size_sect, u_size;
struct drbd_md *md = &mdev->ldev->md;
u32 prev_al_stripe_size_4k;
u32 prev_al_stripes;
sector_t size;
char ppb[10];
void *buffer;
int md_moved, la_size_changed;
enum determine_dev_size rv = DS_UNCHANGED;
@ -847,6 +852,11 @@ enum determine_dev_size drbd_determine_dev_size(struct drbd_conf *mdev, enum dds
* still lock the act_log to not trigger ASSERTs there.
*/
drbd_suspend_io(mdev);
buffer = drbd_md_get_buffer(mdev); /* Lock meta-data IO */
if (!buffer) {
drbd_resume_io(mdev);
return DS_ERROR;
}
/* no wait necessary anymore, actually we could assert that */
wait_event(mdev->al_wait, lc_try_lock(mdev->act_log));
@ -855,7 +865,17 @@ enum determine_dev_size drbd_determine_dev_size(struct drbd_conf *mdev, enum dds
prev_size = mdev->ldev->md.md_size_sect;
la_size_sect = mdev->ldev->md.la_size_sect;
/* TODO: should only be some assert here, not (re)init... */
if (rs) {
/* rs is non NULL if we should change the AL layout only */
prev_al_stripes = md->al_stripes;
prev_al_stripe_size_4k = md->al_stripe_size_4k;
md->al_stripes = rs->al_stripes;
md->al_stripe_size_4k = rs->al_stripe_size / 4;
md->al_size_4k = (u64)rs->al_stripes * rs->al_stripe_size / 4;
}
drbd_md_set_sector_offsets(mdev, mdev->ldev);
rcu_read_lock();
@ -863,6 +883,21 @@ enum determine_dev_size drbd_determine_dev_size(struct drbd_conf *mdev, enum dds
rcu_read_unlock();
size = drbd_new_dev_size(mdev, mdev->ldev, u_size, flags & DDSF_FORCED);
if (size < la_size_sect) {
if (rs && u_size == 0) {
/* Remove "rs &&" later. This check should always be active, but
right now the receiver expects the permissive behavior */
dev_warn(DEV, "Implicit shrink not allowed. "
"Use --size=%llus for explicit shrink.\n",
(unsigned long long)size);
rv = DS_ERROR_SHRINK;
}
if (u_size > size)
rv = DS_ERROR_SPACE_MD;
if (rv != DS_UNCHANGED)
goto err_out;
}
if (drbd_get_capacity(mdev->this_bdev) != size ||
drbd_bm_capacity(mdev) != size) {
int err;
@ -886,38 +921,57 @@ enum determine_dev_size drbd_determine_dev_size(struct drbd_conf *mdev, enum dds
dev_info(DEV, "size = %s (%llu KB)\n", ppsize(ppb, size>>1),
(unsigned long long)size>>1);
}
if (rv == DS_ERROR)
goto out;
if (rv <= DS_ERROR)
goto err_out;
la_size_changed = (la_size_sect != mdev->ldev->md.la_size_sect);
md_moved = prev_first_sect != drbd_md_first_sector(mdev->ldev)
|| prev_size != mdev->ldev->md.md_size_sect;
if (la_size_changed || md_moved) {
int err;
if (la_size_changed || md_moved || rs) {
u32 prev_flags;
drbd_al_shrink(mdev); /* All extents inactive. */
prev_flags = md->flags;
md->flags &= ~MDF_PRIMARY_IND;
drbd_md_write(mdev, buffer);
dev_info(DEV, "Writing the whole bitmap, %s\n",
la_size_changed && md_moved ? "size changed and md moved" :
la_size_changed ? "size changed" : "md moved");
/* next line implicitly does drbd_suspend_io()+drbd_resume_io() */
err = drbd_bitmap_io(mdev, md_moved ? &drbd_bm_write_all : &drbd_bm_write,
"size changed", BM_LOCKED_MASK);
if (err) {
rv = DS_ERROR;
goto out;
}
drbd_md_mark_dirty(mdev);
drbd_bitmap_io(mdev, md_moved ? &drbd_bm_write_all : &drbd_bm_write,
"size changed", BM_LOCKED_MASK);
drbd_initialize_al(mdev, buffer);
md->flags = prev_flags;
drbd_md_write(mdev, buffer);
if (rs)
dev_info(DEV, "Changed AL layout to al-stripes = %d, al-stripe-size-kB = %d\n",
md->al_stripes, md->al_stripe_size_4k * 4);
}
if (size > la_size_sect)
rv = DS_GREW;
if (size < la_size_sect)
rv = DS_SHRUNK;
out:
if (0) {
err_out:
if (rs) {
md->al_stripes = prev_al_stripes;
md->al_stripe_size_4k = prev_al_stripe_size_4k;
md->al_size_4k = (u64)prev_al_stripes * prev_al_stripe_size_4k;
drbd_md_set_sector_offsets(mdev, mdev->ldev);
}
}
lc_unlock(mdev->act_log);
wake_up(&mdev->al_wait);
drbd_md_put_buffer(mdev);
drbd_resume_io(mdev);
return rv;
@ -1618,8 +1672,8 @@ int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info)
!drbd_md_test_flag(mdev->ldev, MDF_CONNECTED_IND))
set_bit(USE_DEGR_WFC_T, &mdev->flags);
dd = drbd_determine_dev_size(mdev, 0);
if (dd == DS_ERROR) {
dd = drbd_determine_dev_size(mdev, 0, NULL);
if (dd <= DS_ERROR) {
retcode = ERR_NOMEM_BITMAP;
goto force_diskless_dec;
} else if (dd == DS_GREW)
@ -2316,6 +2370,7 @@ int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
struct drbd_conf *mdev;
enum drbd_ret_code retcode;
enum determine_dev_size dd;
bool change_al_layout = false;
enum dds_flags ddsf;
sector_t u_size;
int err;
@ -2326,31 +2381,33 @@ int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
if (retcode != NO_ERROR)
goto fail;
mdev = adm_ctx.mdev;
if (!get_ldev(mdev)) {
retcode = ERR_NO_DISK;
goto fail;
}
memset(&rs, 0, sizeof(struct resize_parms));
rs.al_stripes = mdev->ldev->md.al_stripes;
rs.al_stripe_size = mdev->ldev->md.al_stripe_size_4k * 4;
if (info->attrs[DRBD_NLA_RESIZE_PARMS]) {
err = resize_parms_from_attrs(&rs, info);
if (err) {
retcode = ERR_MANDATORY_TAG;
drbd_msg_put_info(from_attrs_err_to_txt(err));
goto fail;
goto fail_ldev;
}
}
mdev = adm_ctx.mdev;
if (mdev->state.conn > C_CONNECTED) {
retcode = ERR_RESIZE_RESYNC;
goto fail;
goto fail_ldev;
}
if (mdev->state.role == R_SECONDARY &&
mdev->state.peer == R_SECONDARY) {
retcode = ERR_NO_PRIMARY;
goto fail;
}
if (!get_ldev(mdev)) {
retcode = ERR_NO_DISK;
goto fail;
goto fail_ldev;
}
if (rs.no_resync && mdev->tconn->agreed_pro_version < 93) {
@ -2369,6 +2426,28 @@ int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
}
}
if (mdev->ldev->md.al_stripes != rs.al_stripes ||
mdev->ldev->md.al_stripe_size_4k != rs.al_stripe_size / 4) {
u32 al_size_k = rs.al_stripes * rs.al_stripe_size;
if (al_size_k > (16 * 1024 * 1024)) {
retcode = ERR_MD_LAYOUT_TOO_BIG;
goto fail_ldev;
}
if (al_size_k < MD_32kB_SECT/2) {
retcode = ERR_MD_LAYOUT_TOO_SMALL;
goto fail_ldev;
}
if (mdev->state.conn != C_CONNECTED) {
retcode = ERR_MD_LAYOUT_CONNECTED;
goto fail_ldev;
}
change_al_layout = true;
}
if (mdev->ldev->known_size != drbd_get_capacity(mdev->ldev->backing_bdev))
mdev->ldev->known_size = drbd_get_capacity(mdev->ldev->backing_bdev);
@ -2384,12 +2463,18 @@ int drbd_adm_resize(struct sk_buff *skb, struct genl_info *info)
}
ddsf = (rs.resize_force ? DDSF_FORCED : 0) | (rs.no_resync ? DDSF_NO_RESYNC : 0);
dd = drbd_determine_dev_size(mdev, ddsf);
dd = drbd_determine_dev_size(mdev, ddsf, change_al_layout ? &rs : NULL);
drbd_md_sync(mdev);
put_ldev(mdev);
if (dd == DS_ERROR) {
retcode = ERR_NOMEM_BITMAP;
goto fail;
} else if (dd == DS_ERROR_SPACE_MD) {
retcode = ERR_MD_LAYOUT_NO_FIT;
goto fail;
} else if (dd == DS_ERROR_SHRINK) {
retcode = ERR_IMPLICIT_SHRINK;
goto fail;
}
if (mdev->state.conn == C_CONNECTED) {

View File

@ -3617,7 +3617,7 @@ static int receive_sizes(struct drbd_tconn *tconn, struct packet_info *pi)
ddsf = be16_to_cpu(p->dds_flags);
if (get_ldev(mdev)) {
dd = drbd_determine_dev_size(mdev, ddsf);
dd = drbd_determine_dev_size(mdev, ddsf, NULL);
put_ldev(mdev);
if (dd == DS_ERROR)
return -EIO;

View File

@ -177,7 +177,11 @@ enum drbd_ret_code {
ERR_NEED_APV_100 = 163,
ERR_NEED_ALLOW_TWO_PRI = 164,
ERR_MD_UNCLEAN = 165,
ERR_MD_LAYOUT_CONNECTED = 166,
ERR_MD_LAYOUT_TOO_BIG = 167,
ERR_MD_LAYOUT_TOO_SMALL = 168,
ERR_MD_LAYOUT_NO_FIT = 169,
ERR_IMPLICIT_SHRINK = 170,
/* insert new ones above this line */
AFTER_LAST_ERR_CODE
};

View File

@ -181,6 +181,8 @@ GENL_struct(DRBD_NLA_RESIZE_PARMS, 7, resize_parms,
__u64_field(1, DRBD_GENLA_F_MANDATORY, resize_size)
__flg_field(2, DRBD_GENLA_F_MANDATORY, resize_force)
__flg_field(3, DRBD_GENLA_F_MANDATORY, no_resync)
__u32_field_def(4, 0 /* OPTIONAL */, al_stripes, DRBD_AL_STRIPES_DEF)
__u32_field_def(5, 0 /* OPTIONAL */, al_stripe_size, DRBD_AL_STRIPE_SIZE_DEF)
)
GENL_struct(DRBD_NLA_STATE_INFO, 8, state_info,

View File

@ -215,4 +215,13 @@
#define DRBD_ALWAYS_ASBP_DEF 0
#define DRBD_USE_RLE_DEF 1
#define DRBD_AL_STRIPES_MIN 1
#define DRBD_AL_STRIPES_MAX 1024
#define DRBD_AL_STRIPES_DEF 1
#define DRBD_AL_STRIPES_SCALE '1'
#define DRBD_AL_STRIPE_SIZE_MIN 4
#define DRBD_AL_STRIPE_SIZE_MAX 16777216
#define DRBD_AL_STRIPE_SIZE_DEF 32
#define DRBD_AL_STRIPE_SIZE_SCALE 'k' /* kilobytes */
#endif