X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fmd%2Fdm-mpath.c;h=24b2b1e32faefc443bf102949a3674689e505b05;hb=37e58df30063e229ee5157f9d1c1fa1d749917c2;hp=c0950a0b5312158909ed7662a308cae9a440d151;hpb=028867ac28e51afc834a5931e7545c022557eded;p=linux-2.6-omap-h63xx.git diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index c0950a0b531..24b2b1e32fa 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -10,6 +10,7 @@ #include "dm-hw-handler.h" #include "dm-bio-list.h" #include "dm-bio-record.h" +#include "dm-uevent.h" #include #include @@ -75,6 +76,8 @@ struct multipath { unsigned queue_io; /* Must we queue all I/O? */ unsigned queue_if_no_path; /* Queue I/O if last path fails? */ unsigned saved_queue_if_no_path;/* Saved state during suspension */ + unsigned pg_init_retries; /* Number of times to retry pg_init */ + unsigned pg_init_count; /* Number of times pg_init called */ struct work_struct process_queued_ios; struct bio_list queued_ios; @@ -225,6 +228,8 @@ static void __switch_pg(struct multipath *m, struct pgpath *pgpath) m->pg_init_required = 0; m->queue_io = 0; } + + m->pg_init_count = 0; } static int __choose_path_in_pg(struct multipath *m, struct priority_group *pg) @@ -390,11 +395,11 @@ static void dispatch_queued_ios(struct multipath *m) r = map_io(m, bio, mpio, 1); if (r < 0) - bio_endio(bio, bio->bi_size, r); + bio_endio(bio, r); else if (r == DM_MAPIO_REMAPPED) generic_make_request(bio); else if (r == DM_MAPIO_REQUEUE) - bio_endio(bio, bio->bi_size, -EIO); + bio_endio(bio, -EIO); bio = next; } @@ -424,6 +429,7 @@ static void process_queued_ios(struct work_struct *work) must_queue = 0; if (m->pg_init_required && !m->pg_init_in_progress) { + m->pg_init_count++; m->pg_init_required = 0; m->pg_init_in_progress = 1; init_required = 1; @@ -689,9 +695,11 @@ static int parse_features(struct arg_set *as, struct multipath *m) int r; unsigned argc; struct dm_target *ti = m->ti; + const char *param_name; static struct param _params[] = { - {0, 1, "invalid number of feature args"}, + {0, 3, "invalid number of feature args"}, + {1, 50, "pg_init_retries must be between 1 and 50"}, }; r = read_param(_params, shift(as), &argc, &ti->error); @@ -701,12 +709,28 @@ static int parse_features(struct arg_set *as, struct multipath *m) if (!argc) return 0; - if (!strnicmp(shift(as), MESG_STR("queue_if_no_path"))) - return queue_if_no_path(m, 1, 0); - else { + do { + param_name = shift(as); + argc--; + + if (!strnicmp(param_name, MESG_STR("queue_if_no_path"))) { + r = queue_if_no_path(m, 1, 0); + continue; + } + + if (!strnicmp(param_name, MESG_STR("pg_init_retries")) && + (argc >= 1)) { + r = read_param(_params + 1, shift(as), + &m->pg_init_retries, &ti->error); + argc--; + continue; + } + ti->error = "Unrecognised multipath feature request"; - return -EINVAL; - } + r = -EINVAL; + } while (argc && !r); + + return r; } static int multipath_ctr(struct dm_target *ti, unsigned int argc, @@ -798,9 +822,6 @@ static int multipath_map(struct dm_target *ti, struct bio *bio, struct dm_mpath_io *mpio; struct multipath *m = (struct multipath *) ti->private; - if (bio_barrier(bio)) - return -EOPNOTSUPP; - mpio = mempool_alloc(m->mpio_pool, GFP_NOIO); dm_bio_record(&mpio->details, bio); @@ -837,6 +858,9 @@ static int fail_path(struct pgpath *pgpath) if (pgpath == m->current_pgpath) m->current_pgpath = NULL; + dm_path_uevent(DM_UEVENT_PATH_FAILED, m->ti, + pgpath->path.dev->name, m->nr_valid_paths); + queue_work(kmultipathd, &m->trigger_event); out: @@ -876,6 +900,9 @@ static int reinstate_path(struct pgpath *pgpath) if (!m->nr_valid_paths++ && m->queue_size) queue_work(kmultipathd, &m->process_queued_ios); + dm_path_uevent(DM_UEVENT_PATH_REINSTATED, m->ti, + pgpath->path.dev->name, m->nr_valid_paths); + queue_work(kmultipathd, &m->trigger_event); out: @@ -978,6 +1005,26 @@ static int bypass_pg_num(struct multipath *m, const char *pgstr, int bypassed) return 0; } +/* + * Should we retry pg_init immediately? + */ +static int pg_init_limit_reached(struct multipath *m, struct pgpath *pgpath) +{ + unsigned long flags; + int limit_reached = 0; + + spin_lock_irqsave(&m->lock, flags); + + if (m->pg_init_count <= m->pg_init_retries) + m->pg_init_required = 1; + else + limit_reached = 1; + + spin_unlock_irqrestore(&m->lock, flags); + + return limit_reached; +} + /* * pg_init must call this when it has completed its initialisation */ @@ -988,8 +1035,14 @@ void dm_pg_init_complete(struct dm_path *path, unsigned err_flags) struct multipath *m = pg->m; unsigned long flags; - /* We insist on failing the path if the PG is already bypassed. */ - if (err_flags && pg->bypassed) + /* + * If requested, retry pg_init until maximum number of retries exceeded. + * If retry not requested and PG already bypassed, always fail the path. + */ + if (err_flags & MP_RETRY) { + if (pg_init_limit_reached(m, pgpath)) + err_flags |= MP_FAIL_PATH; + } else if (err_flags && pg->bypassed) err_flags |= MP_FAIL_PATH; if (err_flags & MP_FAIL_PATH) @@ -999,7 +1052,7 @@ void dm_pg_init_complete(struct dm_path *path, unsigned err_flags) bypass_pg(m, pg, 1); spin_lock_irqsave(&m->lock, flags); - if (err_flags) { + if (err_flags & ~MP_RETRY) { m->current_pgpath = NULL; m->current_pg = NULL; } else if (!m->pg_init_required) @@ -1151,11 +1204,15 @@ static int multipath_status(struct dm_target *ti, status_type_t type, /* Features */ if (type == STATUSTYPE_INFO) - DMEMIT("1 %u ", m->queue_size); - else if (m->queue_if_no_path) - DMEMIT("1 queue_if_no_path "); - else - DMEMIT("0 "); + DMEMIT("2 %u %u ", m->queue_size, m->pg_init_count); + else { + DMEMIT("%u ", m->queue_if_no_path + + (m->pg_init_retries > 0) * 2); + if (m->queue_if_no_path) + DMEMIT("queue_if_no_path "); + if (m->pg_init_retries) + DMEMIT("pg_init_retries %u ", m->pg_init_retries); + } if (hwh->type && hwh->type->status) sz += hwh->type->status(hwh, type, result + sz, maxlen - sz); @@ -1352,15 +1409,14 @@ static int __init dm_multipath_init(void) r = dm_register_target(&multipath_target); if (r < 0) { - DMERR("%s: register failed %d", multipath_target.name, r); + DMERR("register failed %d", r); kmem_cache_destroy(_mpio_cache); return -EINVAL; } kmultipathd = create_workqueue("kmpathd"); if (!kmultipathd) { - DMERR("%s: failed to create workqueue kmpathd", - multipath_target.name); + DMERR("failed to create workqueue kmpathd"); dm_unregister_target(&multipath_target); kmem_cache_destroy(_mpio_cache); return -ENOMEM; @@ -1381,8 +1437,7 @@ static void __exit dm_multipath_exit(void) r = dm_unregister_target(&multipath_target); if (r < 0) - DMERR("%s: target unregister failed %d", - multipath_target.name, r); + DMERR("target unregister failed %d", r); kmem_cache_destroy(_mpio_cache); }