[3/4] btrfs: use btrfs_raid_array[] to calculate the number of parity stripes

Commit Message

Qu Wenruo May 13, 2022, 8:34 a.m. UTC

This makes later expansion on RAID56 based profiles easier.

Signed-off-by: Qu Wenruo <[e-mail]>
---
 fs/btrfs/raid56.c  | 10 ++--------
 fs/btrfs/raid56.h  | 12 ++----------
 fs/btrfs/volumes.c |  7 +++++++
 fs/btrfs/volumes.h |  1 +
 4 files changed, 12 insertions(+), 18 deletions(-)

Comments

Johannes Thumshirn May 13, 2022, 8:56 a.m. UTC | #1

Looks good,
Reviewed-by: Johannes Thumshirn <[e-mail]>

Patch

diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index a5b623ee6fac..068576768925 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -1032,7 +1032,6 @@  static struct btrfs_raid_bio *alloc_rbio(struct btrfs_fs_info *fs_info,
 	const unsigned int stripe_nsectors = stripe_len >> fs_info->sectorsize_bits;
 	const unsigned int num_sectors = stripe_nsectors * real_stripes;
 	struct btrfs_raid_bio *rbio;
-	int nr_data = 0;
 	void *p;
 
 	ASSERT(IS_ALIGNED(stripe_len, PAGE_SIZE));
@@ -1085,14 +1084,9 @@  static struct btrfs_raid_bio *alloc_rbio(struct btrfs_fs_info *fs_info,
 	CONSUME_ALLOC(rbio->finish_pbitmap, BITS_TO_LONGS(stripe_nsectors));
 #undef  CONSUME_ALLOC
 
-	if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID5)
-		nr_data = real_stripes - 1;
-	else if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID6)
-		nr_data = real_stripes - 2;
-	else
-		BUG();
+	ASSERT(btrfs_nr_parity_stripes(bioc->map_type));
+	rbio->nr_data = real_stripes - btrfs_nr_parity_stripes(bioc->map_type);
 
-	rbio->nr_data = nr_data;
 	return rbio;
 }
 
diff --git a/fs/btrfs/raid56.h b/fs/btrfs/raid56.h
index aaad08aefd7d..83a766bcfb17 100644
--- a/fs/btrfs/raid56.h
+++ b/fs/btrfs/raid56.h
@@ -7,19 +7,11 @@ 
 #ifndef BTRFS_RAID56_H
 #define BTRFS_RAID56_H
 
-static inline int nr_parity_stripes(const struct map_lookup *map)
-{
-	if (map->type & BTRFS_BLOCK_GROUP_RAID5)
-		return 1;
-	else if (map->type & BTRFS_BLOCK_GROUP_RAID6)
-		return 2;
-	else
-		return 0;
-}
+#include "volumes.h"
 
 static inline int nr_data_stripes(const struct map_lookup *map)
 {
-	return map->num_stripes - nr_parity_stripes(map);
+	return map->num_stripes - btrfs_nr_parity_stripes(map->type);
 }
 #define RAID5_P_STRIPE ((u64)-2)
 #define RAID6_Q_STRIPE ((u64)-1)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index c6c55ef17000..2ce9140fb955 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6985,6 +6985,13 @@  u64 btrfs_calc_stripe_length(const struct extent_map *em)
 	return div_u64(em->len, data_stripes);
 }
 
+int btrfs_nr_parity_stripes(u64 type)
+{
+	enum btrfs_raid_types index = btrfs_bg_flags_to_raid_index(type);
+
+	return btrfs_raid_array[index].nparity;
+}
+
 #if BITS_PER_LONG == 32
 /*
  * Due to page cache limit, metadata beyond BTRFS_32BIT_MAX_FILE_SIZE
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 1338bc251ff6..2bfe14d75a15 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -602,6 +602,7 @@  int btrfs_is_parity_mirror(struct btrfs_fs_info *fs_info,
 unsigned long btrfs_full_stripe_len(struct btrfs_fs_info *fs_info,
 				    u64 logical);
 u64 btrfs_calc_stripe_length(const struct extent_map *em);
+int btrfs_nr_parity_stripes(u64 type);
 int btrfs_chunk_alloc_add_chunk_item(struct btrfs_trans_handle *trans,
 				     struct btrfs_block_group *bg);
 int btrfs_remove_chunk(struct btrfs_trans_handle *trans, u64 chunk_offset);