dm kcopyd: return void from dm_kcopyd_copy()

dm_kcopyd_copy() only ever returns 0 so there is no need for callers to
account for possible failure.  Same goes for dm_kcopyd_zero().

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

6 files changed, 27 insertions, 63 deletions

diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index 44df244807e5..a53413371725 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -1188,9 +1188,8 @@ static void copy_complete(int read_err, unsigned long write_err, void *context)
         queue_continuation(mg->cache->wq, &mg->k);
 }
 
-static int copy(struct dm_cache_migration *mg, bool promote)
+static void copy(struct dm_cache_migration *mg, bool promote)
 {
-        int r;
         struct dm_io_region o_region, c_region;
         struct cache *cache = mg->cache;
 
@@ -1203,11 +1202,9 @@ static int copy(struct dm_cache_migration *mg, bool promote)
         c_region.count = cache->sectors_per_block;
 
         if (promote)
-                r = dm_kcopyd_copy(cache->copier, &o_region, 1, &c_region, 0, copy_complete, &mg->k);
+                dm_kcopyd_copy(cache->copier, &o_region, 1, &c_region, 0, copy_complete, &mg->k);
         else
-                r = dm_kcopyd_copy(cache->copier, &c_region, 1, &o_region, 0, copy_complete, &mg->k);
-
-        return r;
+                dm_kcopyd_copy(cache->copier, &c_region, 1, &o_region, 0, copy_complete, &mg->k);
 }
 
 static void bio_drop_shared_lock(struct cache *cache, struct bio *bio)
@@ -1449,12 +1446,7 @@ static void mg_full_copy(struct work_struct *ws)
         }
 
         init_continuation(&mg->k, mg_upgrade_lock);
-
-        if (copy(mg, is_policy_promote)) {
-                DMERR_LIMIT("%s: migration copy failed", cache_device_name(cache));
-                mg->k.input = BLK_STS_IOERR;
-                mg_complete(mg, false);
-        }
+        copy(mg, is_policy_promote);
 }
 
 static void mg_copy(struct work_struct *ws)
diff --git a/drivers/md/dm-kcopyd.c b/drivers/md/dm-kcopyd.c
index 3c7547a3c371..cc101f3ec42c 100644
--- a/drivers/md/dm-kcopyd.c
+++ b/drivers/md/dm-kcopyd.c
@@ -741,9 +741,9 @@ static void split_job(struct kcopyd_job *master_job)
         }
 }
 
-int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
-                   unsigned int num_dests, struct dm_io_region *dests,
-                   unsigned int flags, dm_kcopyd_notify_fn fn, void *context)
+void dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
+                    unsigned int num_dests, struct dm_io_region *dests,
+                    unsigned int flags, dm_kcopyd_notify_fn fn, void *context)
 {
         struct kcopyd_job *job;
         int i;
@@ -818,16 +818,14 @@ int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
                 job->progress = 0;
                 split_job(job);
         }
-
-        return 0;
 }
 EXPORT_SYMBOL(dm_kcopyd_copy);
 
-int dm_kcopyd_zero(struct dm_kcopyd_client *kc,
-                   unsigned num_dests, struct dm_io_region *dests,
-                   unsigned flags, dm_kcopyd_notify_fn fn, void *context)
+void dm_kcopyd_zero(struct dm_kcopyd_client *kc,
+                    unsigned num_dests, struct dm_io_region *dests,
+                    unsigned flags, dm_kcopyd_notify_fn fn, void *context)
 {
-        return dm_kcopyd_copy(kc, NULL, num_dests, dests, flags, fn, context);
+        dm_kcopyd_copy(kc, NULL, num_dests, dests, flags, fn, context);
 }
 EXPORT_SYMBOL(dm_kcopyd_zero);
 
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c
index 5903e492bb34..79eab1071ec2 100644
--- a/drivers/md/dm-raid1.c
+++ b/drivers/md/dm-raid1.c
@@ -326,9 +326,8 @@ static void recovery_complete(int read_err, unsigned long write_err,
         dm_rh_recovery_end(reg, !(read_err || write_err));
 }
 
-static int recover(struct mirror_set *ms, struct dm_region *reg)
+static void recover(struct mirror_set *ms, struct dm_region *reg)
 {
-        int r;
         unsigned i;
         struct dm_io_region from, to[DM_KCOPYD_MAX_REGIONS], *dest;
         struct mirror *m;
@@ -367,10 +366,8 @@ static int recover(struct mirror_set *ms, struct dm_region *reg)
         if (!errors_handled(ms))
                 set_bit(DM_KCOPYD_IGNORE_ERROR, &flags);
 
-        r = dm_kcopyd_copy(ms->kcopyd_client, &from, ms->nr_mirrors - 1, to,
-                           flags, recovery_complete, reg);
-
-        return r;
+        dm_kcopyd_copy(ms->kcopyd_client, &from, ms->nr_mirrors - 1, to,
+                       flags, recovery_complete, reg);
 }
 
 static void reset_ms_flags(struct mirror_set *ms)
@@ -388,7 +385,6 @@ static void do_recovery(struct mirror_set *ms)
 {
         struct dm_region *reg;
         struct dm_dirty_log *log = dm_rh_dirty_log(ms->rh);
-        int r;
 
         /*
          * Start quiescing some regions.
@@ -398,11 +394,8 @@ static void do_recovery(struct mirror_set *ms)
         /*
          * Copy any already quiesced regions.
          */
-        while ((reg = dm_rh_recovery_start(ms->rh))) {
-                r = recover(ms, reg);
-                if (r)
-                        dm_rh_recovery_end(reg, 0);
-        }
+        while ((reg = dm_rh_recovery_start(ms->rh)))
+                recover(ms, reg);
 
         /*
          * Update the in sync flag.
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index c44477d7a9ea..5997d6808b57 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -1220,18 +1220,13 @@ static struct dm_thin_new_mapping *get_next_mapping(struct pool *pool)
 static void ll_zero(struct thin_c *tc, struct dm_thin_new_mapping *m,
                     sector_t begin, sector_t end)
 {
-        int r;
         struct dm_io_region to;
 
         to.bdev = tc->pool_dev->bdev;
         to.sector = begin;
         to.count = end - begin;
 
-        r = dm_kcopyd_zero(tc->pool->copier, 1, &to, 0, copy_complete, m);
-        if (r < 0) {
-                DMERR_LIMIT("dm_kcopyd_zero() failed");
-                copy_complete(1, 1, m);
-        }
+        dm_kcopyd_zero(tc->pool->copier, 1, &to, 0, copy_complete, m);
 }
 
 static void remap_and_issue_overwrite(struct thin_c *tc, struct bio *bio,
@@ -1257,7 +1252,6 @@ static void schedule_copy(struct thin_c *tc, dm_block_t virt_block,
                           struct dm_bio_prison_cell *cell, struct bio *bio,
                           sector_t len)
 {
-        int r;
         struct pool *pool = tc->pool;
         struct dm_thin_new_mapping *m = get_next_mapping(pool);
 
@@ -1296,19 +1290,8 @@ static void schedule_copy(struct thin_c *tc, dm_block_t virt_block,
                 to.sector = data_dest * pool->sectors_per_block;
                 to.count = len;
 
-                r = dm_kcopyd_copy(pool->copier, &from, 1, &to,
-                                   0, copy_complete, m);
-                if (r < 0) {
-                        DMERR_LIMIT("dm_kcopyd_copy() failed");
-                        copy_complete(1, 1, m);
-
-                        /*
-                         * We allow the zero to be issued, to simplify the
-                         * error path.  Otherwise we'd need to start
-                         * worrying about decrementing the prepare_actions
-                         * counter.
-                         */
-                }
+                dm_kcopyd_copy(pool->copier, &from, 1, &to,
+                               0, copy_complete, m);
 
                 /*
                  * Do we need to zero a tail region?
diff --git a/drivers/md/dm-zoned-reclaim.c b/drivers/md/dm-zoned-reclaim.c
index 44a119e12f1a..edf4b95eb075 100644
--- a/drivers/md/dm-zoned-reclaim.c
+++ b/drivers/md/dm-zoned-reclaim.c
@@ -161,10 +161,8 @@ static int dmz_reclaim_copy(struct dmz_reclaim *zrc,
 
                 /* Copy the valid region */
                 set_bit(DMZ_RECLAIM_KCOPY, &zrc->flags);
-                ret = dm_kcopyd_copy(zrc->kc, &src, 1, &dst, flags,
-                                     dmz_reclaim_kcopy_end, zrc);
-                if (ret)
-                        return ret;
+                dm_kcopyd_copy(zrc->kc, &src, 1, &dst, flags,
+                               dmz_reclaim_kcopy_end, zrc);
 
                 /* Wait for copy to complete */
                 wait_on_bit_io(&zrc->flags, DMZ_RECLAIM_KCOPY,
diff --git a/include/linux/dm-kcopyd.h b/include/linux/dm-kcopyd.h
index cfac8588ed56..e42de7750c88 100644
--- a/include/linux/dm-kcopyd.h
+++ b/include/linux/dm-kcopyd.h
@@ -62,9 +62,9 @@ void dm_kcopyd_client_destroy(struct dm_kcopyd_client *kc);
 typedef void (*dm_kcopyd_notify_fn)(int read_err, unsigned long write_err,
                                     void *context);
 
-int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
-                   unsigned num_dests, struct dm_io_region *dests,
-                   unsigned flags, dm_kcopyd_notify_fn fn, void *context);
+void dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
+                    unsigned num_dests, struct dm_io_region *dests,
+                    unsigned flags, dm_kcopyd_notify_fn fn, void *context);
 
 /*
  * Prepare a callback and submit it via the kcopyd thread.
@@ -81,9 +81,9 @@ void *dm_kcopyd_prepare_callback(struct dm_kcopyd_client *kc,
                                  dm_kcopyd_notify_fn fn, void *context);
 void dm_kcopyd_do_callback(void *job, int read_err, unsigned long write_err);
 
-int dm_kcopyd_zero(struct dm_kcopyd_client *kc,
-                   unsigned num_dests, struct dm_io_region *dests,
-                   unsigned flags, dm_kcopyd_notify_fn fn, void *context);
+void dm_kcopyd_zero(struct dm_kcopyd_client *kc,
+                    unsigned num_dests, struct dm_io_region *dests,
+                    unsigned flags, dm_kcopyd_notify_fn fn, void *context);
 
 #endif  /* __KERNEL__ */
 #endif  /* _LINUX_DM_KCOPYD_H */