btrfs: remove btrfs_raid_bio::fs_info member

We can grab fs_info reliably from btrfs_raid_bio::bioc, as the bioc is
always passed into alloc_rbio(), and only get released when the raid bio
is released.

Remove btrfs_raid_bio::fs_info member, and cleanup all the @fs_info
parameters for alloc_rbio() callers.
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/raid56.c

@@ -60,7 +60,6 @@ enum btrfs_rbio_ops {
 };
 
 struct btrfs_raid_bio {
-	struct btrfs_fs_info *fs_info;
 	struct btrfs_io_context *bioc;
 
 	/* while we're doing rmw on a stripe
@@ -192,7 +191,7 @@ static void scrub_parity_work(struct btrfs_work *work);
 static void start_async_work(struct btrfs_raid_bio *rbio, btrfs_func_t work_func)
 {
 	btrfs_init_work(&rbio->work, work_func, NULL, NULL);
-	btrfs_queue_work(rbio->fs_info->rmw_workers, &rbio->work);
+	btrfs_queue_work(rbio->bioc->fs_info->rmw_workers, &rbio->work);
 }
 
 /*
@@ -345,7 +344,7 @@ static void __remove_rbio_from_cache(struct btrfs_raid_bio *rbio)
 	if (!test_bit(RBIO_CACHE_BIT, &rbio->flags))
 		return;
 
-	table = rbio->fs_info->stripe_hash_table;
+	table = rbio->bioc->fs_info->stripe_hash_table;
 	h = table->table + bucket;
 
 	/* hold the lock for the bucket because we may be
@@ -400,7 +399,7 @@ static void remove_rbio_from_cache(struct btrfs_raid_bio *rbio)
 	if (!test_bit(RBIO_CACHE_BIT, &rbio->flags))
 		return;
 
-	table = rbio->fs_info->stripe_hash_table;
+	table = rbio->bioc->fs_info->stripe_hash_table;
 
 	spin_lock_irqsave(&table->cache_lock, flags);
 	__remove_rbio_from_cache(rbio);
@@ -460,7 +459,7 @@ static void cache_rbio(struct btrfs_raid_bio *rbio)
 	if (!test_bit(RBIO_CACHE_READY_BIT, &rbio->flags))
 		return;
 
-	table = rbio->fs_info->stripe_hash_table;
+	table = rbio->bioc->fs_info->stripe_hash_table;
 
 	spin_lock_irqsave(&table->cache_lock, flags);
 	spin_lock(&rbio->bio_list_lock);
@@ -668,7 +667,7 @@ static noinline int lock_stripe_add(struct btrfs_raid_bio *rbio)
 	struct btrfs_raid_bio *cache_drop = NULL;
 	int ret = 0;
 
-	h = rbio->fs_info->stripe_hash_table->table + rbio_bucket(rbio);
+	h = rbio->bioc->fs_info->stripe_hash_table->table + rbio_bucket(rbio);
 
 	spin_lock_irqsave(&h->lock, flags);
 	list_for_each_entry(cur, &h->hash_list, hash_list) {
@@ -750,7 +749,7 @@ static noinline void unlock_stripe(struct btrfs_raid_bio *rbio)
 	int keep_cache = 0;
 
 	bucket = rbio_bucket(rbio);
-	h = rbio->fs_info->stripe_hash_table->table + bucket;
+	h = rbio->bioc->fs_info->stripe_hash_table->table + bucket;
 
 	if (list_empty(&rbio->plug_list))
 		cache_rbio(rbio);
@@ -864,7 +863,7 @@ static void rbio_orig_end_io(struct btrfs_raid_bio *rbio, blk_status_t err)
 	struct bio *extra;
 
 	if (rbio->generic_bio_cnt)
-		btrfs_bio_counter_sub(rbio->fs_info, rbio->generic_bio_cnt);
+		btrfs_bio_counter_sub(rbio->bioc->fs_info, rbio->generic_bio_cnt);
 
 	/*
 	 * At this moment, rbio->bio_list is empty, however since rbio does not
@@ -987,7 +986,6 @@ static struct btrfs_raid_bio *alloc_rbio(struct btrfs_fs_info *fs_info,
 	INIT_LIST_HEAD(&rbio->stripe_cache);
 	INIT_LIST_HEAD(&rbio->hash_list);
 	rbio->bioc = bioc;
-	rbio->fs_info = fs_info;
 	rbio->stripe_len = stripe_len;
 	rbio->nr_pages = num_pages;
 	rbio->real_stripes = real_stripes;
@@ -1546,7 +1544,7 @@ static int raid56_rmw_stripe(struct btrfs_raid_bio *rbio)
 		bio->bi_end_io = raid_rmw_end_io;
 		bio->bi_opf = REQ_OP_READ;
 
-		btrfs_bio_wq_end_io(rbio->fs_info, bio, BTRFS_WQ_ENDIO_RAID56);
+		btrfs_bio_wq_end_io(rbio->bioc->fs_info, bio, BTRFS_WQ_ENDIO_RAID56);
 
 		submit_bio(bio);
 	}
@@ -1718,9 +1716,10 @@ static void btrfs_raid_unplug(struct blk_plug_cb *cb, bool from_schedule)
 /*
  * our main entry point for writes from the rest of the FS.
  */
-int raid56_parity_write(struct btrfs_fs_info *fs_info, struct bio *bio,
-			struct btrfs_io_context *bioc, u64 stripe_len)
+int raid56_parity_write(struct bio *bio, struct btrfs_io_context *bioc,
+			u64 stripe_len)
 {
+	struct btrfs_fs_info *fs_info = bioc->fs_info;
 	struct btrfs_raid_bio *rbio;
 	struct btrfs_plug_cb *plug = NULL;
 	struct blk_plug_cb *cb;
@@ -2091,7 +2090,7 @@ static int __raid56_parity_recover(struct btrfs_raid_bio *rbio)
 		bio->bi_end_io = raid_recover_end_io;
 		bio->bi_opf = REQ_OP_READ;
 
-		btrfs_bio_wq_end_io(rbio->fs_info, bio, BTRFS_WQ_ENDIO_RAID56);
+		btrfs_bio_wq_end_io(rbio->bioc->fs_info, bio, BTRFS_WQ_ENDIO_RAID56);
 
 		submit_bio(bio);
 	}
@@ -2115,10 +2114,10 @@ static int __raid56_parity_recover(struct btrfs_raid_bio *rbio)
  * so we assume the bio they send down corresponds to a failed part
  * of the drive.
  */
-int raid56_parity_recover(struct btrfs_fs_info *fs_info, struct bio *bio,
-			  struct btrfs_io_context *bioc, u64 stripe_len,
-			  int mirror_num, int generic_io)
+int raid56_parity_recover(struct bio *bio, struct btrfs_io_context *bioc,
+			  u64 stripe_len, int mirror_num, int generic_io)
 {
+	struct btrfs_fs_info *fs_info = bioc->fs_info;
 	struct btrfs_raid_bio *rbio;
 	int ret;
 
@@ -2220,12 +2219,12 @@ static void read_rebuild_work(struct btrfs_work *work)
  * is those pages just hold metadata or file data with checksum.
  */
 
-struct btrfs_raid_bio *
-raid56_parity_alloc_scrub_rbio(struct btrfs_fs_info *fs_info, struct bio *bio,
-			       struct btrfs_io_context *bioc, u64 stripe_len,
-			       struct btrfs_device *scrub_dev,
-			       unsigned long *dbitmap, int stripe_nsectors)
+struct btrfs_raid_bio *raid56_parity_alloc_scrub_rbio(struct bio *bio,
+				struct btrfs_io_context *bioc,
+				u64 stripe_len, struct btrfs_device *scrub_dev,
+				unsigned long *dbitmap, int stripe_nsectors)
 {
+	struct btrfs_fs_info *fs_info = bioc->fs_info;
 	struct btrfs_raid_bio *rbio;
 	int i;
 
@@ -2633,7 +2632,7 @@ static void raid56_parity_scrub_stripe(struct btrfs_raid_bio *rbio)
 		bio->bi_end_io = raid56_parity_scrub_end_io;
 		bio->bi_opf = REQ_OP_READ;
 
-		btrfs_bio_wq_end_io(rbio->fs_info, bio, BTRFS_WQ_ENDIO_RAID56);
+		btrfs_bio_wq_end_io(rbio->bioc->fs_info, bio, BTRFS_WQ_ENDIO_RAID56);
 
 		submit_bio(bio);
 	}
@@ -2669,9 +2668,10 @@ void raid56_parity_submit_scrub_rbio(struct btrfs_raid_bio *rbio)
 /* The following code is used for dev replace of a missing RAID 5/6 device. */
 
 struct btrfs_raid_bio *
-raid56_alloc_missing_rbio(struct btrfs_fs_info *fs_info, struct bio *bio,
-			  struct btrfs_io_context *bioc, u64 length)
+raid56_alloc_missing_rbio(struct bio *bio, struct btrfs_io_context *bioc,
+			  u64 length)
 {
+	struct btrfs_fs_info *fs_info = bioc->fs_info;
 	struct btrfs_raid_bio *rbio;
 
 	rbio = alloc_rbio(fs_info, bioc, length);

fs/btrfs/raid56.h

@@ -30,25 +30,23 @@ static inline int nr_data_stripes(const struct map_lookup *map)
 struct btrfs_raid_bio;
 struct btrfs_device;
 
-int raid56_parity_recover(struct btrfs_fs_info *fs_info, struct bio *bio,
-			  struct btrfs_io_context *bioc, u64 stripe_len,
-			  int mirror_num, int generic_io);
-int raid56_parity_write(struct btrfs_fs_info *fs_info, struct bio *bio,
-			struct btrfs_io_context *bioc, u64 stripe_len);
+int raid56_parity_recover(struct bio *bio, struct btrfs_io_context *bioc,
+			  u64 stripe_len, int mirror_num, int generic_io);
+int raid56_parity_write(struct bio *bio, struct btrfs_io_context *bioc,
+			u64 stripe_len);
 
 void raid56_add_scrub_pages(struct btrfs_raid_bio *rbio, struct page *page,
 			    u64 logical);
 
-struct btrfs_raid_bio *
-raid56_parity_alloc_scrub_rbio(struct btrfs_fs_info *fs_info, struct bio *bio,
-			       struct btrfs_io_context *bioc, u64 stripe_len,
-			       struct btrfs_device *scrub_dev,
-			       unsigned long *dbitmap, int stripe_nsectors);
+struct btrfs_raid_bio *raid56_parity_alloc_scrub_rbio(struct bio *bio,
+				struct btrfs_io_context *bioc, u64 stripe_len,
+				struct btrfs_device *scrub_dev,
+				unsigned long *dbitmap, int stripe_nsectors);
 void raid56_parity_submit_scrub_rbio(struct btrfs_raid_bio *rbio);
 
 struct btrfs_raid_bio *
-raid56_alloc_missing_rbio(struct btrfs_fs_info *fs_info, struct bio *bio,
-			  struct btrfs_io_context *bioc, u64 length);
+raid56_alloc_missing_rbio(struct bio *bio, struct btrfs_io_context *bioc,
+			  u64 length);
 void raid56_submit_missing_rbio(struct btrfs_raid_bio *rbio);
 
 int btrfs_alloc_stripe_hash_table(struct btrfs_fs_info *info);

fs/btrfs/scrub.c

@@ -1400,7 +1400,7 @@ static int scrub_submit_raid56_bio_wait(struct btrfs_fs_info *fs_info,
 	bio->bi_end_io = scrub_bio_wait_endio;
 
 	mirror_num = spage->sblock->pagev[0]->mirror_num;
-	ret = raid56_parity_recover(fs_info, bio, spage->recover->bioc,
+	ret = raid56_parity_recover(bio, spage->recover->bioc,
 				    spage->recover->map_length,
 				    mirror_num, 0);
 	if (ret)
@@ -2230,7 +2230,7 @@ static void scrub_missing_raid56_pages(struct scrub_block *sblock)
 	bio->bi_private = sblock;
 	bio->bi_end_io = scrub_missing_raid56_end_io;
 
-	rbio = raid56_alloc_missing_rbio(fs_info, bio, bioc, length);
+	rbio = raid56_alloc_missing_rbio(bio, bioc, length);
 	if (!rbio)
 		goto rbio_out;
 
@@ -2846,8 +2846,8 @@ static void scrub_parity_check_and_repair(struct scrub_parity *sparity)
 	bio->bi_private = sparity;
 	bio->bi_end_io = scrub_parity_bio_endio;
 
-	rbio = raid56_parity_alloc_scrub_rbio(fs_info, bio, bioc,
-					      length, sparity->scrub_dev,
+	rbio = raid56_parity_alloc_scrub_rbio(bio, bioc, length,
+					      sparity->scrub_dev,
 					      sparity->dbitmap,
 					      sparity->nsectors);
 	if (!rbio)

fs/btrfs/volumes.c

@@ -6708,11 +6708,10 @@ blk_status_t btrfs_map_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 		/* In this case, map_length has been set to the length of
 		   a single stripe; not the whole write */
 		if (btrfs_op(bio) == BTRFS_MAP_WRITE) {
-			ret = raid56_parity_write(fs_info, bio, bioc,
-						  map_length);
+			ret = raid56_parity_write(bio, bioc, map_length);
 		} else {
-			ret = raid56_parity_recover(fs_info, bio, bioc,
-						    map_length, mirror_num, 1);
+			ret = raid56_parity_recover(bio, bioc, map_length,
+						    mirror_num, 1);
 		}
 
 		btrfs_bio_counter_dec(fs_info);