It is possible that BAT is corrupted on disk but we have a good copy of it in RAM. Add dmsetup message to write it out to file write_bat_to_file. This is very basic interface and it must be used as a last resort.
https://virtuozzo.atlassian.net/browse/PSBM-156501 Signed-off-by: Alexander Atanasov <alexander.atana...@virtuozzo.com> --- drivers/md/dm-ploop-cmd.c | 48 +++++++++++++++++++++++++++++++++++++++ drivers/md/dm-ploop-map.c | 4 ++-- drivers/md/dm-ploop.h | 3 +++ 3 files changed, 53 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-ploop-cmd.c b/drivers/md/dm-ploop-cmd.c index 88519f590148b..71f854c509f82 100644 --- a/drivers/md/dm-ploop-cmd.c +++ b/drivers/md/dm-ploop-cmd.c @@ -280,6 +280,45 @@ static void ploop_make_md_wb(struct ploop *ploop, struct md_page *md) write_unlock_irq(&ploop->bat_rwlock); } +/* write all md to disk */ +static u32 ploop_rewrite_bat_from_memory(struct ploop *ploop) +{ + struct rb_node *node; + struct md_page *md; + struct ploop_index_wb *piwb; + blk_status_t bi_status; + DECLARE_COMPLETION_ONSTACK(comp); + int err; + + ploop_suspend_submitting_pios(ploop); + ploop_for_each_md_page(ploop, md, node) { + /* we have the page and want to write so prepare bat update */ + err = ploop_prepare_bat_update(ploop, md, PIWB_TYPE_ALLOC); + /* does wb_init ploop_index_wb_init */ + if (err) { + /* most likely no memory, notify user he may retry */ + printk(KERN_ERR "MD prepare WB failed: %d\n", err); + } + /* mark md for writeback */ + ploop_make_md_wb(ploop, md); + /* piwb is prepared in md->piwb */ + piwb = md->piwb; + init_completion(&comp); + piwb->comp = ∁ + piwb->comp_bi_status = &bi_status; + /* Write index to disk */ + ploop_index_wb_submit(ploop, piwb); + wait_for_completion(&comp); + /* piwb is freed on completion */ + if (bi_status) { + printk(KERN_ERR "MD WB failed: %d\n", blk_status_to_errno(bi_status)); + } + } + ploop_resume_submitting_pios(ploop); + + return 0; +} + static int ploop_grow_relocate_cluster(struct ploop *ploop, struct ploop_cmd *cmd) { @@ -1086,6 +1125,11 @@ static int ploop_check_delta_before_flip(struct ploop *ploop, struct file *file) return ret; } +static int ploop_write_bat_to_file(struct ploop *ploop) +{ + return ploop_rewrite_bat_from_memory(ploop); +} + static int ploop_flip_upper_deltas(struct ploop *ploop) { struct file *file; @@ -1197,6 +1241,10 @@ int ploop_message(struct dm_target *ti, unsigned int argc, char **argv, if (argc != 1) goto unlock; ret = ploop_flip_upper_deltas(ploop); + } else if (!strcmp(argv[0], "write_bat_to_file")) { + if (argc != 1) + goto unlock; + ret = ploop_write_bat_to_file(ploop); } else { ret = -ENOTSUPP; } diff --git a/drivers/md/dm-ploop-map.c b/drivers/md/dm-ploop-map.c index ea04b3e53567e..7e16005f1e5c9 100644 --- a/drivers/md/dm-ploop-map.c +++ b/drivers/md/dm-ploop-map.c @@ -813,7 +813,7 @@ static void ploop_advance_local_after_bat_wb(struct ploop *ploop, ploop_dispatch_pios(ploop, NULL, &list); } -static void ploop_free_piwb(struct ploop_index_wb *piwb) +void ploop_free_piwb(struct ploop_index_wb *piwb) { ploop_free_pio(piwb->ploop, piwb->pio); put_page(piwb->bat_page); @@ -889,7 +889,7 @@ static void ploop_bat_write_complete(struct ploop_index_wb *piwb, ploop_put_piwb(piwb); } -static int ploop_prepare_bat_update(struct ploop *ploop, struct md_page *md, +int ploop_prepare_bat_update(struct ploop *ploop, struct md_page *md, enum piwb_type type) { u32 i, off, last, *bat_entries; diff --git a/drivers/md/dm-ploop.h b/drivers/md/dm-ploop.h index db36687c81696..67dbf8abd4e41 100644 --- a/drivers/md/dm-ploop.h +++ b/drivers/md/dm-ploop.h @@ -559,6 +559,8 @@ extern void ploop_free_md_page(struct md_page *md); extern void ploop_free_md_pages_tree(struct rb_root *root); extern bool ploop_try_update_bat_entry(struct ploop *ploop, u32 clu, u8 level, u32 dst_clu); +extern int ploop_prepare_bat_update(struct ploop *ploop, struct md_page *md, + enum piwb_type type); extern int ploop_add_delta(struct ploop *ploop, u32 level, struct file *file, bool is_raw); @@ -597,6 +599,7 @@ extern int ploop_read_delta_metadata(struct ploop *ploop, struct file *file, struct rb_root *md_root, u32 *delta_nr_be); extern void ploop_index_wb_init(struct ploop_index_wb *piwb, struct ploop *ploop); +extern void ploop_free_piwb(struct ploop_index_wb *piwb); extern void ploop_call_rw_iter(struct file *file, loff_t pos, unsigned rw, struct iov_iter *iter, struct pio *pio); extern void ploop_enospc_timer(struct timer_list *timer); -- 2.43.0 _______________________________________________ Devel mailing list Devel@openvz.org https://lists.openvz.org/mailman/listinfo/devel
