It's used only during initial block group reading to map physical
address of super block to a list of logical ones. Make it private to
block-group.c and while at it add proper kernel doc.
Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx>
---
fs/btrfs/block-group.c | 82 ++++++++++++++++++++++++++++++++++++++++++
fs/btrfs/volumes.c | 69 -----------------------------------
fs/btrfs/volumes.h | 2 --
3 files changed, 82 insertions(+), 71 deletions(-)
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index d96561d1ce90..902c246a9d38 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -14,6 +14,7 @@
#include "sysfs.h"
#include "tree-log.h"
#include "delalloc-space.h"
+#include "raid56.h"
/*
* Return target flags in extended format or 0 if restripe for this chunk_type
@@ -1516,6 +1517,87 @@ static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
write_sequnlock(&fs_info->profiles_lock);
}
+/*
+ * btrfs_rmap_block - Maps a particular @physical disk address to a list of @logical
+ * addresses. Used primarily to exclude those portions of a block group that
+ * contain super block copies.
+ *
+ * chunk_start - Logical address of block group
+ * physical - Physical address to map to logical addresses
+ * logical - Return array of logical addresses which map to @physical
+ * naddrs - Length of @logical
+ * stripe_len - size of IO stripe for the given block group
+ */
+EXPORT_FOR_TESTS
+int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
+ u64 physical, u64 **logical, int *naddrs, int *stripe_len)
+{
+ struct extent_map *em;
+ struct map_lookup *map;
+ u64 *buf;
+ u64 bytenr;
+ u64 length;
+ u64 stripe_nr;
+ u64 rmap_len;
+ int i, j, nr = 0;
+
+ em = btrfs_get_chunk_map(fs_info, chunk_start, 1);
+ if (IS_ERR(em))
+ return -EIO;
+
+ map = em->map_lookup;
+ length = em->len;
+ rmap_len = map->stripe_len;
+
+ if (map->type & BTRFS_BLOCK_GROUP_RAID10)
+ length = div_u64(length, map->num_stripes / map->sub_stripes);
+ else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
+ length = div_u64(length, map->num_stripes);
+ else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+ length = div_u64(length, nr_data_stripes(map));
+ rmap_len = map->stripe_len * nr_data_stripes(map);
+ }
+
+ buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS);
+ BUG_ON(!buf); /* -ENOMEM */
+
+ for (i = 0; i < map->num_stripes; i++) {
+ if (map->stripes[i].physical > physical ||
+ map->stripes[i].physical + length <= physical)
+ continue;
+
+ stripe_nr = physical - map->stripes[i].physical;
+ stripe_nr = div64_u64(stripe_nr, map->stripe_len);
+
+ if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
+ stripe_nr = stripe_nr * map->num_stripes + i;
+ stripe_nr = div_u64(stripe_nr, map->sub_stripes);
+ } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
+ stripe_nr = stripe_nr * map->num_stripes + i;
+ } /* else if RAID[56], multiply by nr_data_stripes().
+ * Alternatively, just use rmap_len below instead of
+ * map->stripe_len */
+
+ bytenr = chunk_start + stripe_nr * rmap_len;
+ WARN_ON(nr >= map->num_stripes);
+ for (j = 0; j < nr; j++) {
+ if (buf[j] == bytenr)
+ break;
+ }
+ if (j == nr) {
+ WARN_ON(nr >= map->num_stripes);
+ buf[nr++] = bytenr;
+ }
+ }
+
+ *logical = buf;
+ *naddrs = nr;
+ *stripe_len = rmap_len;
+
+ free_extent_map(em);
+ return 0;
+}
+
static int exclude_super_stripes(struct btrfs_block_group *cache)
{
struct btrfs_fs_info *fs_info = cache->fs_info;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index d8e5560db285..a1a7b543e465 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6107,75 +6107,6 @@ int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
return __btrfs_map_block(fs_info, op, logical, length, bbio_ret, 0, 1);
}
-int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
- u64 physical, u64 **logical, int *naddrs, int *stripe_len)
-{
- struct extent_map *em;
- struct map_lookup *map;
- u64 *buf;
- u64 bytenr;
- u64 length;
- u64 stripe_nr;
- u64 rmap_len;
- int i, j, nr = 0;
-
- em = btrfs_get_chunk_map(fs_info, chunk_start, 1);
- if (IS_ERR(em))
- return -EIO;
-
- map = em->map_lookup;
- length = em->len;
- rmap_len = map->stripe_len;
-
- if (map->type & BTRFS_BLOCK_GROUP_RAID10)
- length = div_u64(length, map->num_stripes / map->sub_stripes);
- else if (map->type & BTRFS_BLOCK_GROUP_RAID0)
- length = div_u64(length, map->num_stripes);
- else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
- length = div_u64(length, nr_data_stripes(map));
- rmap_len = map->stripe_len * nr_data_stripes(map);
- }
-
- buf = kcalloc(map->num_stripes, sizeof(u64), GFP_NOFS);
- BUG_ON(!buf); /* -ENOMEM */
-
- for (i = 0; i < map->num_stripes; i++) {
- if (map->stripes[i].physical > physical ||
- map->stripes[i].physical + length <= physical)
- continue;
-
- stripe_nr = physical - map->stripes[i].physical;
- stripe_nr = div64_u64(stripe_nr, map->stripe_len);
-
- if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
- stripe_nr = stripe_nr * map->num_stripes + i;
- stripe_nr = div_u64(stripe_nr, map->sub_stripes);
- } else if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
- stripe_nr = stripe_nr * map->num_stripes + i;
- } /* else if RAID[56], multiply by nr_data_stripes().
- * Alternatively, just use rmap_len below instead of
- * map->stripe_len */
-
- bytenr = chunk_start + stripe_nr * rmap_len;
- WARN_ON(nr >= map->num_stripes);
- for (j = 0; j < nr; j++) {
- if (buf[j] == bytenr)
- break;
- }
- if (j == nr) {
- WARN_ON(nr >= map->num_stripes);
- buf[nr++] = bytenr;
- }
- }
-
- *logical = buf;
- *naddrs = nr;
- *stripe_len = rmap_len;
-
- free_extent_map(em);
- return 0;
-}
-
static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio)
{
bio->bi_private = bbio->private;
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index fc1b564b9cfe..12a7e0dd26bd 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -417,8 +417,6 @@ int btrfs_map_sblock(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
struct btrfs_bio **bbio_ret);
int btrfs_get_io_geometry(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
u64 logical, u64 len, struct btrfs_io_geometry *io_geom);
-int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,
- u64 physical, u64 **logical, int *naddrs, int *stripe_len);
int btrfs_read_sys_array(struct btrfs_fs_info *fs_info);
int btrfs_read_chunk_tree(struct btrfs_fs_info *fs_info);
int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 type);
--
2.17.1
