From 950e1951d452d08a5bd95d82d4cad7fa97fa4464 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Thu, 19 Nov 2009 13:54:56 +0100 Subject: Accept failed paths for multipath maps References: bnc#458037,bnc#458393 Patch-mainline: Not yet The multipath kernel module is rejecting any map with an invalid device. However, as the multipathd is processing the events serially it will try to push a map with invalid devices if more than one device failed at the same time. So we can as well accept those maps and make sure to mark the paths as down. Signed-off-by: Hannes Reinecke --- --- drivers/md/dm-mpath.c | 71 ++++++++++++++++++++++++++++++++++++++++---------- drivers/md/dm-mpath.h | 1 drivers/md/dm-table.c | 7 +++- 3 files changed, 64 insertions(+), 15 deletions(-) --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -146,7 +146,8 @@ static void deactivate_path(struct work_ struct pgpath *pgpath = container_of(work, struct pgpath, deactivate_path); - blk_abort_queue(pgpath->path.dev->bdev->bd_disk->queue); + if (pgpath->path.dev) + blk_abort_queue(pgpath->path.dev->bdev->bd_disk->queue); } static struct priority_group *alloc_priority_group(void) @@ -275,6 +276,11 @@ static int __choose_path_in_pg(struct mu m->current_pgpath = path_to_pgpath(path); + if (!m->current_pgpath->path.dev) { + m->current_pgpath = NULL; + return -ENODEV; + } + if (m->current_pg != pg) __switch_pg(m, m->current_pgpath); @@ -593,6 +599,7 @@ static struct pgpath *parse_path(struct { int r; struct pgpath *p; + char *path; struct multipath *m = ti->private; /* we need at least a path arg */ @@ -605,14 +612,37 @@ static struct pgpath *parse_path(struct if (!p) return ERR_PTR(-ENOMEM); - r = dm_get_device(ti, shift(as), dm_table_get_mode(ti->table), + path = shift(as); + r = dm_get_device(ti, path, dm_table_get_mode(ti->table), &p->path.dev); if (r) { - ti->error = "error getting device"; - goto bad; + unsigned major, minor; + + /* Try to add a failed device */ + if (r == -ENXIO && sscanf(path, "%u:%u", &major, &minor) == 2) { + dev_t dev; + + /* Extract the major/minor numbers */ + dev = MKDEV(major, minor); + if (MAJOR(dev) != major || MINOR(dev) != minor) { + /* Nice try, didn't work */ + DMWARN("Invalid device path %s", path); + ti->error = "error converting devnum"; + goto bad; + } + DMWARN("adding disabled device %d:%d", major, minor); + p->path.dev = NULL; + format_dev_t(p->path.pdev, dev); + p->is_active = 0; + } else { + ti->error = "error getting device"; + goto bad; + } + } else { + memcpy(p->path.pdev, p->path.dev->name, 16); } - if (m->hw_handler_name) { + if (m->hw_handler_name && p->path.dev) { struct request_queue *q = bdev_get_queue(p->path.dev->bdev); r = scsi_dh_attach(q, m->hw_handler_name); @@ -649,6 +679,11 @@ static struct pgpath *parse_path(struct goto bad; } + if (!p->is_active) { + ps->type->fail_path(ps, &p->path); + p->fail_count++; + m->nr_valid_paths--; + } return p; bad: @@ -976,7 +1011,7 @@ static int fail_path(struct pgpath *pgpa if (!pgpath->is_active) goto out; - DMWARN("Failing path %s.", pgpath->path.dev->name); + DMWARN("Failing path %s.", pgpath->path.pdev); pgpath->pg->ps.type->fail_path(&pgpath->pg->ps, &pgpath->path); pgpath->is_active = 0; @@ -988,7 +1023,7 @@ static int fail_path(struct pgpath *pgpa m->current_pgpath = NULL; dm_path_uevent(DM_UEVENT_PATH_FAILED, m->ti, - pgpath->path.dev->name, m->nr_valid_paths); + pgpath->path.pdev, m->nr_valid_paths); schedule_work(&m->trigger_event); queue_work(kmultipathd, &pgpath->deactivate_path); @@ -1013,6 +1048,12 @@ static int reinstate_path(struct pgpath if (pgpath->is_active) goto out; + if (!pgpath->path.dev) { + DMWARN("Cannot reinstate disabled path %s", pgpath->path.pdev); + r = -ENODEV; + goto out; + } + if (!pgpath->pg->ps.type->reinstate_path) { DMWARN("Reinstate path not supported by path selector %s", pgpath->pg->ps.type->name); @@ -1035,7 +1076,7 @@ static int reinstate_path(struct pgpath } dm_path_uevent(DM_UEVENT_PATH_REINSTATED, m->ti, - pgpath->path.dev->name, m->nr_valid_paths); + pgpath->path.pdev, m->nr_valid_paths); schedule_work(&m->trigger_event); @@ -1055,6 +1096,9 @@ static int action_dev(struct multipath * struct pgpath *pgpath; struct priority_group *pg; + if (!dev) + return 0; + list_for_each_entry(pg, &m->priority_groups, list) { list_for_each_entry(pgpath, &pg->pgpaths, list) { if (pgpath->path.dev == dev) @@ -1239,8 +1283,9 @@ static void activate_path(struct work_st struct pgpath *pgpath = container_of(work, struct pgpath, activate_path); - scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev), - pg_init_done, pgpath); + if (pgpath->path.dev) + scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev), + pg_init_done, pgpath); } /* @@ -1415,7 +1460,7 @@ static int multipath_status(struct dm_ta pg->ps.type->info_args); list_for_each_entry(p, &pg->pgpaths, list) { - DMEMIT("%s %s %u ", p->path.dev->name, + DMEMIT("%s %s %u ", p->path.pdev, p->is_active ? "A" : "F", p->fail_count); if (pg->ps.type->status) @@ -1441,7 +1486,7 @@ static int multipath_status(struct dm_ta pg->ps.type->table_args); list_for_each_entry(p, &pg->pgpaths, list) { - DMEMIT("%s ", p->path.dev->name); + DMEMIT("%s ", p->path.pdev); if (pg->ps.type->status) sz += pg->ps.type->status(&pg->ps, &p->path, type, result + sz, @@ -1533,7 +1578,7 @@ static int multipath_ioctl(struct dm_tar if (!m->current_pgpath) __choose_pgpath(m, 0); - if (m->current_pgpath) { + if (m->current_pgpath && m->current_pgpath->path.dev) { bdev = m->current_pgpath->path.dev->bdev; mode = m->current_pgpath->path.dev->mode; } --- a/drivers/md/dm-mpath.h +++ b/drivers/md/dm-mpath.h @@ -12,6 +12,7 @@ struct dm_dev; struct dm_path { + char pdev[16]; /* Requested physical device */ struct dm_dev *dev; /* Read-only */ void *pscontext; /* For path-selector use */ }; --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -538,9 +538,12 @@ int dm_get_device(struct dm_target *ti, */ void dm_put_device(struct dm_target *ti, struct dm_dev *d) { - struct dm_dev_internal *dd = container_of(d, struct dm_dev_internal, - dm_dev); + struct dm_dev_internal *dd; + if (!d) + return; + + dd = container_of(d, struct dm_dev_internal, dm_dev); if (atomic_dec_and_test(&dd->count)) { close_dev(dd, ti->table->md); list_del(&dd->list);