1 files changed, 106 insertions, 11 deletions

diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c
index 9c96530ea6d5..dabb84f7ab8a 100644
--- a/drivers/nvdimm/btt.c
+++ b/drivers/nvdimm/btt.c
@@ -31,6 +31,11 @@ enum log_ent_request {
         LOG_OLD_ENT
 };
 
+static u64 adjust_initial_offset(struct nd_btt *nd_btt, u64 offset)
+{
+        return offset + nd_btt->initial_offset;
+}
+
 static int arena_read_bytes(struct arena_info *arena, resource_size_t offset,
                 void *buf, size_t n, unsigned long flags)
 {
@@ -38,7 +43,7 @@ static int arena_read_bytes(struct arena_info *arena, resource_size_t offset,
         struct nd_namespace_common *ndns = nd_btt->ndns;
 
         /* arena offsets may be shifted from the base of the device */
-        offset += arena->nd_btt->initial_offset;
+        offset = adjust_initial_offset(nd_btt, offset);
         return nvdimm_read_bytes(ndns, offset, buf, n, flags);
 }
 
@@ -49,7 +54,7 @@ static int arena_write_bytes(struct arena_info *arena, resource_size_t offset,
         struct nd_namespace_common *ndns = nd_btt->ndns;
 
         /* arena offsets may be shifted from the base of the device */
-        offset += arena->nd_btt->initial_offset;
+        offset = adjust_initial_offset(nd_btt, offset);
         return nvdimm_write_bytes(ndns, offset, buf, n, flags);
 }
 
@@ -381,7 +386,9 @@ static int btt_flog_write(struct arena_info *arena, u32 lane, u32 sub,
         arena->freelist[lane].sub = 1 - arena->freelist[lane].sub;
         if (++(arena->freelist[lane].seq) == 4)
                 arena->freelist[lane].seq = 1;
-        arena->freelist[lane].block = le32_to_cpu(ent->old_map);
+        if (ent_e_flag(ent->old_map))
+                arena->freelist[lane].has_err = 1;
+        arena->freelist[lane].block = le32_to_cpu(ent_lba(ent->old_map));
 
         return ret;
 }
@@ -480,6 +487,40 @@ static int btt_log_init(struct arena_info *arena)
         return ret;
 }
 
+static u64 to_namespace_offset(struct arena_info *arena, u64 lba)
+{
+        return arena->dataoff + ((u64)lba * arena->internal_lbasize);
+}
+
+static int arena_clear_freelist_error(struct arena_info *arena, u32 lane)
+{
+        int ret = 0;
+
+        if (arena->freelist[lane].has_err) {
+                void *zero_page = page_address(ZERO_PAGE(0));
+                u32 lba = arena->freelist[lane].block;
+                u64 nsoff = to_namespace_offset(arena, lba);
+                unsigned long len = arena->sector_size;
+
+                mutex_lock(&arena->err_lock);
+
+                while (len) {
+                        unsigned long chunk = min(len, PAGE_SIZE);
+
+                        ret = arena_write_bytes(arena, nsoff, zero_page,
+                                chunk, 0);
+                        if (ret)
+                                break;
+                        len -= chunk;
+                        nsoff += chunk;
+                        if (len == 0)
+                                arena->freelist[lane].has_err = 0;
+                }
+                mutex_unlock(&arena->err_lock);
+        }
+        return ret;
+}
+
 static int btt_freelist_init(struct arena_info *arena)
 {
         int old, new, ret;
@@ -505,6 +546,16 @@ static int btt_freelist_init(struct arena_info *arena)
                 arena->freelist[i].seq = nd_inc_seq(le32_to_cpu(log_new.seq));
                 arena->freelist[i].block = le32_to_cpu(log_new.old_map);
 
+                /*
+                 * FIXME: if error clearing fails during init, we want to make
+                 * the BTT read-only
+                 */
+                if (ent_e_flag(log_new.old_map)) {
+                        ret = arena_clear_freelist_error(arena, i);
+                        if (ret)
+                                WARN_ONCE(1, "Unable to clear known errors\n");
+                }
+
                 /* This implies a newly created or untouched flog entry */
                 if (log_new.old_map == log_new.new_map)
                         continue;
@@ -525,7 +576,6 @@ static int btt_freelist_init(struct arena_info *arena)
                         if (ret)
                                 return ret;
                 }
-
         }
 
         return 0;
@@ -695,6 +745,7 @@ static int discover_arenas(struct btt *btt)
                 arena->external_lba_start = cur_nlba;
                 parse_arena_meta(arena, super, cur_off);
 
+                mutex_init(&arena->err_lock);
                 ret = btt_freelist_init(arena);
                 if (ret)
                         goto out;
@@ -905,11 +956,6 @@ static void unlock_map(struct arena_info *arena, u32 premap)
         spin_unlock(&arena->map_locks[idx].lock);
 }
 
-static u64 to_namespace_offset(struct arena_info *arena, u64 lba)
-{
-        return arena->dataoff + ((u64)lba * arena->internal_lbasize);
-}
-
 static int btt_data_read(struct arena_info *arena, struct page *page,
                         unsigned int off, u32 lba, u32 len)
 {
@@ -1067,8 +1113,14 @@ static int btt_read_pg(struct btt *btt, struct bio_integrity_payload *bip,
                 }
 
                 ret = btt_data_read(arena, page, off, postmap, cur_len);
-                if (ret)
+                if (ret) {
+                        int rc;
+
+                        /* Media error - set the e_flag */
+                        rc = btt_map_write(arena, premap, postmap, 0, 1,
+                                NVDIMM_IO_ATOMIC);
                         goto out_rtt;
+                }
 
                 if (bip) {
                         ret = btt_rw_integrity(btt, bip, arena, postmap, READ);
@@ -1093,6 +1145,21 @@ static int btt_read_pg(struct btt *btt, struct bio_integrity_payload *bip,
         return ret;
 }
 
+/*
+ * Normally, arena_{read,write}_bytes will take care of the initial offset
+ * adjustment, but in the case of btt_is_badblock, where we query is_bad_pmem,
+ * we need the final, raw namespace offset here
+ */
+static bool btt_is_badblock(struct btt *btt, struct arena_info *arena,
+                u32 postmap)
+{
+        u64 nsoff = adjust_initial_offset(arena->nd_btt,
+                        to_namespace_offset(arena, postmap));
+        sector_t phys_sector = nsoff >> 9;
+
+        return is_bad_pmem(btt->phys_bb, phys_sector, arena->internal_lbasize);
+}
+
 static int btt_write_pg(struct btt *btt, struct bio_integrity_payload *bip,
                         sector_t sector, struct page *page, unsigned int off,
                         unsigned int len)
@@ -1105,7 +1172,9 @@ static int btt_write_pg(struct btt *btt, struct bio_integrity_payload *bip,
 
         while (len) {
                 u32 cur_len;
+                int e_flag;
 
+ retry:
                 lane = nd_region_acquire_lane(btt->nd_region);
 
                 ret = lba_to_arena(btt, sector, &premap, &arena);
@@ -1118,6 +1187,21 @@ static int btt_write_pg(struct btt *btt, struct bio_integrity_payload *bip,
                         goto out_lane;
                 }
 
+                if (btt_is_badblock(btt, arena, arena->freelist[lane].block))
+                        arena->freelist[lane].has_err = 1;
+
+                if (mutex_is_locked(&arena->err_lock)
+                                || arena->freelist[lane].has_err) {
+                        nd_region_release_lane(btt->nd_region, lane);
+
+                        ret = arena_clear_freelist_error(arena, lane);
+                        if (ret)
+                                return ret;
+
+                        /* OK to acquire a different lane/free block */
+                        goto retry;
+                }
+
                 new_postmap = arena->freelist[lane].block;
 
                 /* Wait if the new block is being read from */
@@ -1143,7 +1227,7 @@ static int btt_write_pg(struct btt *btt, struct bio_integrity_payload *bip,
                 }
 
                 lock_map(arena, premap);
-                ret = btt_map_read(arena, premap, &old_postmap, NULL, NULL,
+                ret = btt_map_read(arena, premap, &old_postmap, NULL, &e_flag,
                                 NVDIMM_IO_ATOMIC);
                 if (ret)
                         goto out_map;
@@ -1151,6 +1235,8 @@ static int btt_write_pg(struct btt *btt, struct bio_integrity_payload *bip,
                         ret = -EIO;
                         goto out_map;
                 }
+                if (e_flag)
+                        set_e_flag(old_postmap);
 
                 log.lba = cpu_to_le32(premap);
                 log.old_map = cpu_to_le32(old_postmap);
@@ -1169,6 +1255,12 @@ static int btt_write_pg(struct btt *btt, struct bio_integrity_payload *bip,
                 unlock_map(arena, premap);
                 nd_region_release_lane(btt->nd_region, lane);
 
+                if (e_flag) {
+                        ret = arena_clear_freelist_error(arena, lane);
+                        if (ret)
+                                return ret;
+                }
+
                 len -= cur_len;
                 off += cur_len;
                 sector += btt->sector_size >> SECTOR_SHIFT;
@@ -1349,6 +1441,7 @@ static struct btt *btt_init(struct nd_btt *nd_btt, unsigned long long rawsize,
 {
         int ret;
         struct btt *btt;
+        struct nd_namespace_io *nsio;
         struct device *dev = &nd_btt->dev;
 
         btt = devm_kzalloc(dev, sizeof(struct btt), GFP_KERNEL);
@@ -1362,6 +1455,8 @@ static struct btt *btt_init(struct nd_btt *nd_btt, unsigned long long rawsize,
         INIT_LIST_HEAD(&btt->arena_list);
         mutex_init(&btt->init_lock);
         btt->nd_region = nd_region;
+        nsio = to_nd_namespace_io(&nd_btt->ndns->dev);
+        btt->phys_bb = &nsio->bb;
 
         ret = discover_arenas(btt);
         if (ret) {