mirror of https://gitee.com/openkylin/linux.git
- Fix DM multipath by restoring full path selector functionality for
bio-based configurations that don't haave a SCSI device handler. - Fix dm-btree removal to ensure non-root btree nodes have at least (max_entries / 3) entries. This resolves userspace thin_check utility's report of "too few entries in btree_node". - Fix both the DM thin-provisioning and dm-clone targets to properly flush the data device prior to metadata commit. This resolves the potential for inconsistency across a power loss event when the data device has a volatile writeback cache. - Small documentation fixes to dm-clone and dm-integrity. -----BEGIN PGP SIGNATURE----- iQFHBAABCAAxFiEEJfWUX4UqZ4x1O2wixSPxCi2dA1oFAl3yU6sTHHNuaXR6ZXJA cmVkaGF0LmNvbQAKCRDFI/EKLZ0DWvO9B/0dsIxL09sWSHPe+wuzy7WXAOCHVm04 27dloxNzgXGFT5ftvU+JpLParOtDfJ2ral2BVGExjGzMs4QP8ZLrn5UuTFuR7nXi FDaypaCelRsh1/204bKDgb22vaZIAZFu7Rz2YsAzWqpCJZDjN5cgy9xz4GmCvXRt R13Qq8Dia4scR/y+xCkm5s4wH2xGz1CDmpSPzbLTpTfkMfY5yzp6Gzaipj4Fwq78 dDERNZNuabVr2o8mt8OGd/s1h4QtiJps1J8NV2He5C3Bf8daaFVkHDCl75+P2KQC ++VaIS/l1TfcOyDJmoztg7w2gmLkTxEskVpN/UQD/Ut9D5m7P9S7uaQg =6t9f -----END PGP SIGNATURE----- Merge tag 'for-5.5/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper fixes from Mike Snitzer: - Fix DM multipath by restoring full path selector functionality for bio-based configurations that don't haave a SCSI device handler. - Fix dm-btree removal to ensure non-root btree nodes have at least (max_entries / 3) entries. This resolves userspace thin_check utility's report of "too few entries in btree_node". - Fix both the DM thin-provisioning and dm-clone targets to properly flush the data device prior to metadata commit. This resolves the potential for inconsistency across a power loss event when the data device has a volatile writeback cache. - Small documentation fixes to dm-clone and dm-integrity. * tag 'for-5.5/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: docs: dm-integrity: remove reference to ARC4 dm thin: Flush data device before committing metadata dm thin metadata: Add support for a pre-commit callback dm clone: Flush destination device before committing metadata dm clone metadata: Use a two phase commit dm clone metadata: Track exact changes per transaction dm btree: increase rebalance threshold in __rebalance2() dm: add dm-clone to the documentation index dm mpath: remove harmful bio-based optimization
This commit is contained in:
Linus Torvalds
commit
15da849c91
|
|
@ -144,7 +144,7 @@ journal_crypt:algorithm(:key) (the key is optional)
|
|||
Encrypt the journal using given algorithm to make sure that the
|
||||
attacker can't read the journal. You can use a block cipher here
|
||||
(such as "cbc(aes)") or a stream cipher (for example "chacha20",
|
||||
"salsa20", "ctr(aes)" or "ecb(arc4)").
|
||||
"salsa20" or "ctr(aes)").
|
||||
|
||||
The journal contains history of last writes to the block device,
|
||||
an attacker reading the journal could see the last sector nubmers
|
||||
|
|
|
|||
|
|
@ -8,6 +8,7 @@ Device Mapper
|
|||
cache-policies
|
||||
cache
|
||||
delay
|
||||
dm-clone
|
||||
dm-crypt
|
||||
dm-dust
|
||||
dm-flakey
|
||||
|
|
|
|||
|
|
@ -67,23 +67,34 @@ struct superblock_disk {
|
|||
* To save constantly doing look ups on disk we keep an in core copy of the
|
||||
* on-disk bitmap, the region_map.
|
||||
*
|
||||
* To further reduce metadata I/O overhead we use a second bitmap, the dmap
|
||||
* (dirty bitmap), which tracks the dirty words, i.e. longs, of the region_map.
|
||||
* In order to track which regions are hydrated during a metadata transaction,
|
||||
* we use a second set of bitmaps, the dmap (dirty bitmap), which includes two
|
||||
* bitmaps, namely dirty_regions and dirty_words. The dirty_regions bitmap
|
||||
* tracks the regions that got hydrated during the current metadata
|
||||
* transaction. The dirty_words bitmap tracks the dirty words, i.e. longs, of
|
||||
* the dirty_regions bitmap.
|
||||
*
|
||||
* This allows us to precisely track the regions that were hydrated during the
|
||||
* current metadata transaction and update the metadata accordingly, when we
|
||||
* commit the current transaction. This is important because dm-clone should
|
||||
* only commit the metadata of regions that were properly flushed to the
|
||||
* destination device beforehand. Otherwise, in case of a crash, we could end
|
||||
* up with a corrupted dm-clone device.
|
||||
*
|
||||
* When a region finishes hydrating dm-clone calls
|
||||
* dm_clone_set_region_hydrated(), or for discard requests
|
||||
* dm_clone_cond_set_range(), which sets the corresponding bits in region_map
|
||||
* and dmap.
|
||||
*
|
||||
* During a metadata commit we scan the dmap for dirty region_map words (longs)
|
||||
* and update accordingly the on-disk metadata. Thus, we don't have to flush to
|
||||
* disk the whole region_map. We can just flush the dirty region_map words.
|
||||
* During a metadata commit we scan dmap->dirty_words and dmap->dirty_regions
|
||||
* and update the on-disk metadata accordingly. Thus, we don't have to flush to
|
||||
* disk the whole region_map. We can just flush the dirty region_map bits.
|
||||
*
|
||||
* We use a dirty bitmap, which is smaller than the original region_map, to
|
||||
* reduce the amount of memory accesses during a metadata commit. As dm-bitset
|
||||
* accesses the on-disk bitmap in 64-bit word granularity, there is no
|
||||
* significant benefit in tracking the dirty region_map bits with a smaller
|
||||
* granularity.
|
||||
* We use the helper dmap->dirty_words bitmap, which is smaller than the
|
||||
* original region_map, to reduce the amount of memory accesses during a
|
||||
* metadata commit. Moreover, as dm-bitset also accesses the on-disk bitmap in
|
||||
* 64-bit word granularity, the dirty_words bitmap helps us avoid useless disk
|
||||
* accesses.
|
||||
*
|
||||
* We could update directly the on-disk bitmap, when dm-clone calls either
|
||||
* dm_clone_set_region_hydrated() or dm_clone_cond_set_range(), buts this
|
||||
|
|
@ -92,12 +103,13 @@ struct superblock_disk {
|
|||
* e.g., in a hooked overwrite bio's completion routine, and further reduce the
|
||||
* I/O completion latency.
|
||||
*
|
||||
* We maintain two dirty bitmaps. During a metadata commit we atomically swap
|
||||
* the currently used dmap with the unused one. This allows the metadata update
|
||||
* functions to run concurrently with an ongoing commit.
|
||||
* We maintain two dirty bitmap sets. During a metadata commit we atomically
|
||||
* swap the currently used dmap with the unused one. This allows the metadata
|
||||
* update functions to run concurrently with an ongoing commit.
|
||||
*/
|
||||
struct dirty_map {
|
||||
unsigned long *dirty_words;
|
||||
unsigned long *dirty_regions;
|
||||
unsigned int changed;
|
||||
};
|
||||
|
||||
|
|
@ -115,6 +127,9 @@ struct dm_clone_metadata {
|
|||
struct dirty_map dmap[2];
|
||||
struct dirty_map *current_dmap;
|
||||
|
||||
/* Protected by lock */
|
||||
struct dirty_map *committing_dmap;
|
||||
|
||||
/*
|
||||
* In core copy of the on-disk bitmap to save constantly doing look ups
|
||||
* on disk.
|
||||
|
|
@ -461,34 +476,53 @@ static size_t bitmap_size(unsigned long nr_bits)
|
|||
return BITS_TO_LONGS(nr_bits) * sizeof(long);
|
||||
}
|
||||
|
||||
static int __dirty_map_init(struct dirty_map *dmap, unsigned long nr_words,
|
||||
unsigned long nr_regions)
|
||||
{
|
||||
dmap->changed = 0;
|
||||
|
||||
dmap->dirty_words = kvzalloc(bitmap_size(nr_words), GFP_KERNEL);
|
||||
if (!dmap->dirty_words)
|
||||
return -ENOMEM;
|
||||
|
||||
dmap->dirty_regions = kvzalloc(bitmap_size(nr_regions), GFP_KERNEL);
|
||||
if (!dmap->dirty_regions) {
|
||||
kvfree(dmap->dirty_words);
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void __dirty_map_exit(struct dirty_map *dmap)
|
||||
{
|
||||
kvfree(dmap->dirty_words);
|
||||
kvfree(dmap->dirty_regions);
|
||||
}
|
||||
|
||||
static int dirty_map_init(struct dm_clone_metadata *cmd)
|
||||
{
|
||||
cmd->dmap[0].changed = 0;
|
||||
cmd->dmap[0].dirty_words = kvzalloc(bitmap_size(cmd->nr_words), GFP_KERNEL);
|
||||
|
||||
if (!cmd->dmap[0].dirty_words) {
|
||||
if (__dirty_map_init(&cmd->dmap[0], cmd->nr_words, cmd->nr_regions)) {
|
||||
DMERR("Failed to allocate dirty bitmap");
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
cmd->dmap[1].changed = 0;
|
||||
cmd->dmap[1].dirty_words = kvzalloc(bitmap_size(cmd->nr_words), GFP_KERNEL);
|
||||
|
||||
if (!cmd->dmap[1].dirty_words) {
|
||||
if (__dirty_map_init(&cmd->dmap[1], cmd->nr_words, cmd->nr_regions)) {
|
||||
DMERR("Failed to allocate dirty bitmap");
|
||||
kvfree(cmd->dmap[0].dirty_words);
|
||||
__dirty_map_exit(&cmd->dmap[0]);
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
cmd->current_dmap = &cmd->dmap[0];
|
||||
cmd->committing_dmap = NULL;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void dirty_map_exit(struct dm_clone_metadata *cmd)
|
||||
{
|
||||
kvfree(cmd->dmap[0].dirty_words);
|
||||
kvfree(cmd->dmap[1].dirty_words);
|
||||
__dirty_map_exit(&cmd->dmap[0]);
|
||||
__dirty_map_exit(&cmd->dmap[1]);
|
||||
}
|
||||
|
||||
static int __load_bitset_in_core(struct dm_clone_metadata *cmd)
|
||||
|
|
@ -633,21 +667,23 @@ unsigned long dm_clone_find_next_unhydrated_region(struct dm_clone_metadata *cmd
|
|||
return find_next_zero_bit(cmd->region_map, cmd->nr_regions, start);
|
||||
}
|
||||
|
||||
static int __update_metadata_word(struct dm_clone_metadata *cmd, unsigned long word)
|
||||
static int __update_metadata_word(struct dm_clone_metadata *cmd,
|
||||
unsigned long *dirty_regions,
|
||||
unsigned long word)
|
||||
{
|
||||
int r;
|
||||
unsigned long index = word * BITS_PER_LONG;
|
||||
unsigned long max_index = min(cmd->nr_regions, (word + 1) * BITS_PER_LONG);
|
||||
|
||||
while (index < max_index) {
|
||||
if (test_bit(index, cmd->region_map)) {
|
||||
if (test_bit(index, dirty_regions)) {
|
||||
r = dm_bitset_set_bit(&cmd->bitset_info, cmd->bitset_root,
|
||||
index, &cmd->bitset_root);
|
||||
|
||||
if (r) {
|
||||
DMERR("dm_bitset_set_bit failed");
|
||||
return r;
|
||||
}
|
||||
__clear_bit(index, dirty_regions);
|
||||
}
|
||||
index++;
|
||||
}
|
||||
|
|
@ -721,7 +757,7 @@ static int __flush_dmap(struct dm_clone_metadata *cmd, struct dirty_map *dmap)
|
|||
if (word == cmd->nr_words)
|
||||
break;
|
||||
|
||||
r = __update_metadata_word(cmd, word);
|
||||
r = __update_metadata_word(cmd, dmap->dirty_regions, word);
|
||||
|
||||
if (r)
|
||||
return r;
|
||||
|
|
@ -743,15 +779,17 @@ static int __flush_dmap(struct dm_clone_metadata *cmd, struct dirty_map *dmap)
|
|||
return 0;
|
||||
}
|
||||
|
||||
int dm_clone_metadata_commit(struct dm_clone_metadata *cmd)
|
||||
int dm_clone_metadata_pre_commit(struct dm_clone_metadata *cmd)
|
||||
{
|
||||
int r = -EPERM;
|
||||
int r = 0;
|
||||
struct dirty_map *dmap, *next_dmap;
|
||||
|
||||
down_write(&cmd->lock);
|
||||
|
||||
if (cmd->fail_io || dm_bm_is_read_only(cmd->bm))
|
||||
if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) {
|
||||
r = -EPERM;
|
||||
goto out;
|
||||
}
|
||||
|
||||
/* Get current dirty bitmap */
|
||||
dmap = cmd->current_dmap;
|
||||
|
|
@ -763,7 +801,7 @@ int dm_clone_metadata_commit(struct dm_clone_metadata *cmd)
|
|||
* The last commit failed, so we don't have a clean dirty-bitmap to
|
||||
* use.
|
||||
*/
|
||||
if (WARN_ON(next_dmap->changed)) {
|
||||
if (WARN_ON(next_dmap->changed || cmd->committing_dmap)) {
|
||||
r = -EINVAL;
|
||||
goto out;
|
||||
}
|
||||
|
|
@ -773,11 +811,33 @@ int dm_clone_metadata_commit(struct dm_clone_metadata *cmd)
|
|||
cmd->current_dmap = next_dmap;
|
||||
spin_unlock_irq(&cmd->bitmap_lock);
|
||||
|
||||
/*
|
||||
* No one is accessing the old dirty bitmap anymore, so we can flush
|
||||
* it.
|
||||
*/
|
||||
r = __flush_dmap(cmd, dmap);
|
||||
/* Set old dirty bitmap as currently committing */
|
||||
cmd->committing_dmap = dmap;
|
||||
out:
|
||||
up_write(&cmd->lock);
|
||||
|
||||
return r;
|
||||
}
|
||||
|
||||
int dm_clone_metadata_commit(struct dm_clone_metadata *cmd)
|
||||
{
|
||||
int r = -EPERM;
|
||||
|
||||
down_write(&cmd->lock);
|
||||
|
||||
if (cmd->fail_io || dm_bm_is_read_only(cmd->bm))
|
||||
goto out;
|
||||
|
||||
if (WARN_ON(!cmd->committing_dmap)) {
|
||||
r = -EINVAL;
|
||||
goto out;
|
||||
}
|
||||
|
||||
r = __flush_dmap(cmd, cmd->committing_dmap);
|
||||
if (!r) {
|
||||
/* Clear committing dmap */
|
||||
cmd->committing_dmap = NULL;
|
||||
}
|
||||
out:
|
||||
up_write(&cmd->lock);
|
||||
|
||||
|
|
@ -802,6 +862,7 @@ int dm_clone_set_region_hydrated(struct dm_clone_metadata *cmd, unsigned long re
|
|||
dmap = cmd->current_dmap;
|
||||
|
||||
__set_bit(word, dmap->dirty_words);
|
||||
__set_bit(region_nr, dmap->dirty_regions);
|
||||
__set_bit(region_nr, cmd->region_map);
|
||||
dmap->changed = 1;
|
||||
|
||||
|
|
@ -830,6 +891,7 @@ int dm_clone_cond_set_range(struct dm_clone_metadata *cmd, unsigned long start,
|
|||
if (!test_bit(region_nr, cmd->region_map)) {
|
||||
word = region_nr / BITS_PER_LONG;
|
||||
__set_bit(word, dmap->dirty_words);
|
||||
__set_bit(region_nr, dmap->dirty_regions);
|
||||
__set_bit(region_nr, cmd->region_map);
|
||||
dmap->changed = 1;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -75,7 +75,23 @@ void dm_clone_metadata_close(struct dm_clone_metadata *cmd);
|
|||
|
||||
/*
|
||||
* Commit dm-clone metadata to disk.
|
||||
*
|
||||
* We use a two phase commit:
|
||||
*
|
||||
* 1. dm_clone_metadata_pre_commit(): Prepare the current transaction for
|
||||
* committing. After this is called, all subsequent metadata updates, done
|
||||
* through either dm_clone_set_region_hydrated() or
|
||||
* dm_clone_cond_set_range(), will be part of the **next** transaction.
|
||||
*
|
||||
* 2. dm_clone_metadata_commit(): Actually commit the current transaction to
|
||||
* disk and start a new transaction.
|
||||
*
|
||||
* This allows dm-clone to flush the destination device after step (1) to
|
||||
* ensure that all freshly hydrated regions, for which we are updating the
|
||||
* metadata, are properly written to non-volatile storage and won't be lost in
|
||||
* case of a crash.
|
||||
*/
|
||||
int dm_clone_metadata_pre_commit(struct dm_clone_metadata *cmd);
|
||||
int dm_clone_metadata_commit(struct dm_clone_metadata *cmd);
|
||||
|
||||
/*
|
||||
|
|
@ -112,6 +128,7 @@ int dm_clone_metadata_abort(struct dm_clone_metadata *cmd);
|
|||
* Switches metadata to a read only mode. Once read-only mode has been entered
|
||||
* the following functions will return -EPERM:
|
||||
*
|
||||
* dm_clone_metadata_pre_commit()
|
||||
* dm_clone_metadata_commit()
|
||||
* dm_clone_set_region_hydrated()
|
||||
* dm_clone_cond_set_range()
|
||||
|
|
|
|||
|
|
@ -86,6 +86,12 @@ struct clone {
|
|||
|
||||
struct dm_clone_metadata *cmd;
|
||||
|
||||
/*
|
||||
* bio used to flush the destination device, before committing the
|
||||
* metadata.
|
||||
*/
|
||||
struct bio flush_bio;
|
||||
|
||||
/* Region hydration hash table */
|
||||
struct hash_table_bucket *ht;
|
||||
|
||||
|
|
@ -1108,10 +1114,13 @@ static bool need_commit_due_to_time(struct clone *clone)
|
|||
/*
|
||||
* A non-zero return indicates read-only or fail mode.
|
||||
*/
|
||||
static int commit_metadata(struct clone *clone)
|
||||
static int commit_metadata(struct clone *clone, bool *dest_dev_flushed)
|
||||
{
|
||||
int r = 0;
|
||||
|
||||
if (dest_dev_flushed)
|
||||
*dest_dev_flushed = false;
|
||||
|
||||
mutex_lock(&clone->commit_lock);
|
||||
|
||||
if (!dm_clone_changed_this_transaction(clone->cmd))
|
||||
|
|
@ -1122,8 +1131,26 @@ static int commit_metadata(struct clone *clone)
|
|||
goto out;
|
||||
}
|
||||
|
||||
r = dm_clone_metadata_commit(clone->cmd);
|
||||
r = dm_clone_metadata_pre_commit(clone->cmd);
|
||||
if (unlikely(r)) {
|
||||
__metadata_operation_failed(clone, "dm_clone_metadata_pre_commit", r);
|
||||
goto out;
|
||||
}
|
||||
|
||||
bio_reset(&clone->flush_bio);
|
||||
bio_set_dev(&clone->flush_bio, clone->dest_dev->bdev);
|
||||
clone->flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
|
||||
|
||||
r = submit_bio_wait(&clone->flush_bio);
|
||||
if (unlikely(r)) {
|
||||
__metadata_operation_failed(clone, "flush destination device", r);
|
||||
goto out;
|
||||
}
|
||||
|
||||
if (dest_dev_flushed)
|
||||
*dest_dev_flushed = true;
|
||||
|
||||
r = dm_clone_metadata_commit(clone->cmd);
|
||||
if (unlikely(r)) {
|
||||
__metadata_operation_failed(clone, "dm_clone_metadata_commit", r);
|
||||
goto out;
|
||||
|
|
@ -1194,6 +1221,7 @@ static void process_deferred_bios(struct clone *clone)
|
|||
static void process_deferred_flush_bios(struct clone *clone)
|
||||
{
|
||||
struct bio *bio;
|
||||
bool dest_dev_flushed;
|
||||
struct bio_list bios = BIO_EMPTY_LIST;
|
||||
struct bio_list bio_completions = BIO_EMPTY_LIST;
|
||||
|
||||
|
|
@ -1213,7 +1241,7 @@ static void process_deferred_flush_bios(struct clone *clone)
|
|||
!(dm_clone_changed_this_transaction(clone->cmd) && need_commit_due_to_time(clone)))
|
||||
return;
|
||||
|
||||
if (commit_metadata(clone)) {
|
||||
if (commit_metadata(clone, &dest_dev_flushed)) {
|
||||
bio_list_merge(&bios, &bio_completions);
|
||||
|
||||
while ((bio = bio_list_pop(&bios)))
|
||||
|
|
@ -1227,8 +1255,17 @@ static void process_deferred_flush_bios(struct clone *clone)
|
|||
while ((bio = bio_list_pop(&bio_completions)))
|
||||
bio_endio(bio);
|
||||
|
||||
while ((bio = bio_list_pop(&bios)))
|
||||
while ((bio = bio_list_pop(&bios))) {
|
||||
if ((bio->bi_opf & REQ_PREFLUSH) && dest_dev_flushed) {
|
||||
/* We just flushed the destination device as part of
|
||||
* the metadata commit, so there is no reason to send
|
||||
* another flush.
|
||||
*/
|
||||
bio_endio(bio);
|
||||
} else {
|
||||
generic_make_request(bio);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
static void do_worker(struct work_struct *work)
|
||||
|
|
@ -1400,7 +1437,7 @@ static void clone_status(struct dm_target *ti, status_type_t type,
|
|||
|
||||
/* Commit to ensure statistics aren't out-of-date */
|
||||
if (!(status_flags & DM_STATUS_NOFLUSH_FLAG) && !dm_suspended(ti))
|
||||
(void) commit_metadata(clone);
|
||||
(void) commit_metadata(clone, NULL);
|
||||
|
||||
r = dm_clone_get_free_metadata_block_count(clone->cmd, &nr_free_metadata_blocks);
|
||||
|
||||
|
|
@ -1834,6 +1871,7 @@ static int clone_ctr(struct dm_target *ti, unsigned int argc, char **argv)
|
|||
bio_list_init(&clone->deferred_flush_completions);
|
||||
clone->hydration_offset = 0;
|
||||
atomic_set(&clone->hydrations_in_flight, 0);
|
||||
bio_init(&clone->flush_bio, NULL, 0);
|
||||
|
||||
clone->wq = alloc_workqueue("dm-" DM_MSG_PREFIX, WQ_MEM_RECLAIM, 0);
|
||||
if (!clone->wq) {
|
||||
|
|
@ -1907,6 +1945,7 @@ static void clone_dtr(struct dm_target *ti)
|
|||
struct clone *clone = ti->private;
|
||||
|
||||
mutex_destroy(&clone->commit_lock);
|
||||
bio_uninit(&clone->flush_bio);
|
||||
|
||||
for (i = 0; i < clone->nr_ctr_args; i++)
|
||||
kfree(clone->ctr_args[i]);
|
||||
|
|
@ -1961,7 +2000,7 @@ static void clone_postsuspend(struct dm_target *ti)
|
|||
wait_event(clone->hydration_stopped, !atomic_read(&clone->hydrations_in_flight));
|
||||
flush_workqueue(clone->wq);
|
||||
|
||||
(void) commit_metadata(clone);
|
||||
(void) commit_metadata(clone, NULL);
|
||||
}
|
||||
|
||||
static void clone_resume(struct dm_target *ti)
|
||||
|
|
|
|||
|
|
@ -599,45 +599,10 @@ static struct pgpath *__map_bio(struct multipath *m, struct bio *bio)
|
|||
return pgpath;
|
||||
}
|
||||
|
||||
static struct pgpath *__map_bio_fast(struct multipath *m, struct bio *bio)
|
||||
{
|
||||
struct pgpath *pgpath;
|
||||
unsigned long flags;
|
||||
|
||||
/* Do we need to select a new pgpath? */
|
||||
/*
|
||||
* FIXME: currently only switching path if no path (due to failure, etc)
|
||||
* - which negates the point of using a path selector
|
||||
*/
|
||||
pgpath = READ_ONCE(m->current_pgpath);
|
||||
if (!pgpath)
|
||||
pgpath = choose_pgpath(m, bio->bi_iter.bi_size);
|
||||
|
||||
if (!pgpath) {
|
||||
if (test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) {
|
||||
/* Queue for the daemon to resubmit */
|
||||
spin_lock_irqsave(&m->lock, flags);
|
||||
bio_list_add(&m->queued_bios, bio);
|
||||
spin_unlock_irqrestore(&m->lock, flags);
|
||||
queue_work(kmultipathd, &m->process_queued_bios);
|
||||
|
||||
return ERR_PTR(-EAGAIN);
|
||||
}
|
||||
return NULL;
|
||||
}
|
||||
|
||||
return pgpath;
|
||||
}
|
||||
|
||||
static int __multipath_map_bio(struct multipath *m, struct bio *bio,
|
||||
struct dm_mpath_io *mpio)
|
||||
{
|
||||
struct pgpath *pgpath;
|
||||
|
||||
if (!m->hw_handler_name)
|
||||
pgpath = __map_bio_fast(m, bio);
|
||||
else
|
||||
pgpath = __map_bio(m, bio);
|
||||
struct pgpath *pgpath = __map_bio(m, bio);
|
||||
|
||||
if (IS_ERR(pgpath))
|
||||
return DM_MAPIO_SUBMITTED;
|
||||
|
|
|
|||
|
|
@ -188,6 +188,15 @@ struct dm_pool_metadata {
|
|||
unsigned long flags;
|
||||
sector_t data_block_size;
|
||||
|
||||
/*
|
||||
* Pre-commit callback.
|
||||
*
|
||||
* This allows the thin provisioning target to run a callback before
|
||||
* the metadata are committed.
|
||||
*/
|
||||
dm_pool_pre_commit_fn pre_commit_fn;
|
||||
void *pre_commit_context;
|
||||
|
||||
/*
|
||||
* We reserve a section of the metadata for commit overhead.
|
||||
* All reported space does *not* include this.
|
||||
|
|
@ -826,6 +835,14 @@ static int __commit_transaction(struct dm_pool_metadata *pmd)
|
|||
if (unlikely(!pmd->in_service))
|
||||
return 0;
|
||||
|
||||
if (pmd->pre_commit_fn) {
|
||||
r = pmd->pre_commit_fn(pmd->pre_commit_context);
|
||||
if (r < 0) {
|
||||
DMERR("pre-commit callback failed");
|
||||
return r;
|
||||
}
|
||||
}
|
||||
|
||||
r = __write_changed_details(pmd);
|
||||
if (r < 0)
|
||||
return r;
|
||||
|
|
@ -892,6 +909,8 @@ struct dm_pool_metadata *dm_pool_metadata_open(struct block_device *bdev,
|
|||
pmd->in_service = false;
|
||||
pmd->bdev = bdev;
|
||||
pmd->data_block_size = data_block_size;
|
||||
pmd->pre_commit_fn = NULL;
|
||||
pmd->pre_commit_context = NULL;
|
||||
|
||||
r = __create_persistent_data_objects(pmd, format_device);
|
||||
if (r) {
|
||||
|
|
@ -2044,6 +2063,16 @@ int dm_pool_register_metadata_threshold(struct dm_pool_metadata *pmd,
|
|||
return r;
|
||||
}
|
||||
|
||||
void dm_pool_register_pre_commit_callback(struct dm_pool_metadata *pmd,
|
||||
dm_pool_pre_commit_fn fn,
|
||||
void *context)
|
||||
{
|
||||
pmd_write_lock_in_core(pmd);
|
||||
pmd->pre_commit_fn = fn;
|
||||
pmd->pre_commit_context = context;
|
||||
pmd_write_unlock(pmd);
|
||||
}
|
||||
|
||||
int dm_pool_metadata_set_needs_check(struct dm_pool_metadata *pmd)
|
||||
{
|
||||
int r = -EINVAL;
|
||||
|
|
|
|||
|
|
@ -230,6 +230,13 @@ bool dm_pool_metadata_needs_check(struct dm_pool_metadata *pmd);
|
|||
*/
|
||||
void dm_pool_issue_prefetches(struct dm_pool_metadata *pmd);
|
||||
|
||||
/* Pre-commit callback */
|
||||
typedef int (*dm_pool_pre_commit_fn)(void *context);
|
||||
|
||||
void dm_pool_register_pre_commit_callback(struct dm_pool_metadata *pmd,
|
||||
dm_pool_pre_commit_fn fn,
|
||||
void *context);
|
||||
|
||||
/*----------------------------------------------------------------*/
|
||||
|
||||
#endif
|
||||
|
|
|
|||
|
|
@ -328,6 +328,7 @@ struct pool_c {
|
|||
dm_block_t low_water_blocks;
|
||||
struct pool_features requested_pf; /* Features requested during table load */
|
||||
struct pool_features adjusted_pf; /* Features used after adjusting for constituent devices */
|
||||
struct bio flush_bio;
|
||||
};
|
||||
|
||||
/*
|
||||
|
|
@ -2383,8 +2384,16 @@ static void process_deferred_bios(struct pool *pool)
|
|||
while ((bio = bio_list_pop(&bio_completions)))
|
||||
bio_endio(bio);
|
||||
|
||||
while ((bio = bio_list_pop(&bios)))
|
||||
while ((bio = bio_list_pop(&bios))) {
|
||||
/*
|
||||
* The data device was flushed as part of metadata commit,
|
||||
* so complete redundant flushes immediately.
|
||||
*/
|
||||
if (bio->bi_opf & REQ_PREFLUSH)
|
||||
bio_endio(bio);
|
||||
else
|
||||
generic_make_request(bio);
|
||||
}
|
||||
}
|
||||
|
||||
static void do_worker(struct work_struct *ws)
|
||||
|
|
@ -3115,6 +3124,7 @@ static void pool_dtr(struct dm_target *ti)
|
|||
__pool_dec(pt->pool);
|
||||
dm_put_device(ti, pt->metadata_dev);
|
||||
dm_put_device(ti, pt->data_dev);
|
||||
bio_uninit(&pt->flush_bio);
|
||||
kfree(pt);
|
||||
|
||||
mutex_unlock(&dm_thin_pool_table.mutex);
|
||||
|
|
@ -3180,6 +3190,29 @@ static void metadata_low_callback(void *context)
|
|||
dm_table_event(pool->ti->table);
|
||||
}
|
||||
|
||||
/*
|
||||
* We need to flush the data device **before** committing the metadata.
|
||||
*
|
||||
* This ensures that the data blocks of any newly inserted mappings are
|
||||
* properly written to non-volatile storage and won't be lost in case of a
|
||||
* crash.
|
||||
*
|
||||
* Failure to do so can result in data corruption in the case of internal or
|
||||
* external snapshots and in the case of newly provisioned blocks, when block
|
||||
* zeroing is enabled.
|
||||
*/
|
||||
static int metadata_pre_commit_callback(void *context)
|
||||
{
|
||||
struct pool_c *pt = context;
|
||||
struct bio *flush_bio = &pt->flush_bio;
|
||||
|
||||
bio_reset(flush_bio);
|
||||
bio_set_dev(flush_bio, pt->data_dev->bdev);
|
||||
flush_bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
|
||||
|
||||
return submit_bio_wait(flush_bio);
|
||||
}
|
||||
|
||||
static sector_t get_dev_size(struct block_device *bdev)
|
||||
{
|
||||
return i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
|
||||
|
|
@ -3348,6 +3381,7 @@ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv)
|
|||
pt->data_dev = data_dev;
|
||||
pt->low_water_blocks = low_water_blocks;
|
||||
pt->adjusted_pf = pt->requested_pf = pf;
|
||||
bio_init(&pt->flush_bio, NULL, 0);
|
||||
ti->num_flush_bios = 1;
|
||||
|
||||
/*
|
||||
|
|
@ -3374,6 +3408,10 @@ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv)
|
|||
if (r)
|
||||
goto out_flags_changed;
|
||||
|
||||
dm_pool_register_pre_commit_callback(pt->pool->pmd,
|
||||
metadata_pre_commit_callback,
|
||||
pt);
|
||||
|
||||
pt->callbacks.congested_fn = pool_is_congested;
|
||||
dm_table_add_target_callbacks(ti->table, &pt->callbacks);
|
||||
|
||||
|
|
|
|||
|
|
@ -203,7 +203,13 @@ static void __rebalance2(struct dm_btree_info *info, struct btree_node *parent,
|
|||
struct btree_node *right = r->n;
|
||||
uint32_t nr_left = le32_to_cpu(left->header.nr_entries);
|
||||
uint32_t nr_right = le32_to_cpu(right->header.nr_entries);
|
||||
unsigned threshold = 2 * merge_threshold(left) + 1;
|
||||
/*
|
||||
* Ensure the number of entries in each child will be greater
|
||||
* than or equal to (max_entries / 3 + 1), so no matter which
|
||||
* child is used for removal, the number will still be not
|
||||
* less than (max_entries / 3).
|
||||
*/
|
||||
unsigned int threshold = 2 * (merge_threshold(left) + 1);
|
||||
|
||||
if (nr_left + nr_right < threshold) {
|
||||
/*
|
||||
|
|
|
|||
Loading…
Reference in New Issue