#include "dm-hw-handler.h"
#include "dm-bio-list.h"
#include "dm-bio-record.h"
+#include "dm-uevent.h"
#include <linux/ctype.h>
#include <linux/init.h>
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;
struct work_struct trigger_event;
/*
- * We must use a mempool of mpath_io structs so that we
+ * We must use a mempool of dm_mpath_io structs so that we
* can resubmit bios on error.
*/
mempool_t *mpio_pool;
/*
* Context information attached to each bio we process.
*/
-struct mpath_io {
+struct dm_mpath_io {
struct pgpath *pgpath;
struct dm_bio_details details;
};
return pgpath;
}
-static inline void free_pgpath(struct pgpath *pgpath)
+static void free_pgpath(struct pgpath *pgpath)
{
kfree(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)
dm_noflush_suspending(m->ti));
}
-static int map_io(struct multipath *m, struct bio *bio, struct mpath_io *mpio,
- unsigned was_queued)
+static int map_io(struct multipath *m, struct bio *bio,
+ struct dm_mpath_io *mpio, unsigned was_queued)
{
int r = DM_MAPIO_REMAPPED;
unsigned long flags;
int r;
unsigned long flags;
struct bio *bio = NULL, *next;
- struct mpath_io *mpio;
+ struct dm_mpath_io *mpio;
union map_info *info;
spin_lock_irqsave(&m->lock, flags);
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;
}
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;
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);
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,
union map_info *map_context)
{
int r;
- struct mpath_io *mpio;
+ 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);
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:
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:
}
/*
+ * 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
*/
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)
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)
* end_io handling
*/
static int do_end_io(struct multipath *m, struct bio *bio,
- int error, struct mpath_io *mpio)
+ int error, struct dm_mpath_io *mpio)
{
struct hw_handler *hwh = &m->hw_handler;
unsigned err_flags = MP_FAIL_PATH; /* Default behavior */
static int multipath_end_io(struct dm_target *ti, struct bio *bio,
int error, union map_info *map_context)
{
- struct multipath *m = (struct multipath *) ti->private;
- struct mpath_io *mpio = (struct mpath_io *) map_context->ptr;
+ struct multipath *m = ti->private;
+ struct dm_mpath_io *mpio = map_context->ptr;
struct pgpath *pgpath = mpio->pgpath;
struct path_selector *ps;
int r;
/* 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);
int r;
/* allocate a slab for the dm_ios */
- _mpio_cache = kmem_cache_create("dm_mpath", sizeof(struct mpath_io),
- 0, 0, NULL, NULL);
+ _mpio_cache = KMEM_CACHE(dm_mpath_io, 0);
if (!_mpio_cache)
return -ENOMEM;
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;
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);
}