btrfs: root->fs_info cleanup, add fs_info convenience variables

In routines where someptr->fs_info is referenced multiple times, we
introduce a convenience variable.  This makes the code considerably
more readable.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 39 insertions, 41 deletions

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 6834ff8dc0ab..8aef00b0ff84 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -489,8 +489,8 @@ struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace)
 			sctx->bios[i]->next_free = -1;
 	}
 	sctx->first_free = 0;
-	sctx->nodesize = dev->fs_info->nodesize;
-	sctx->sectorsize = dev->fs_info->sectorsize;
+	sctx->nodesize = fs_info->nodesize;
+	sctx->sectorsize = fs_info->sectorsize;
 	atomic_set(&sctx->bios_in_flight, 0);
 	atomic_set(&sctx->workers_pending, 0);
 	atomic_set(&sctx->cancel_req, 0);
@@ -789,6 +789,7 @@ out:
 
 static void scrub_fixup_nodatasum(struct btrfs_work *work)
 {
+	struct btrfs_fs_info *fs_info;
 	int ret;
 	struct scrub_fixup_nodatasum *fixup;
 	struct scrub_ctx *sctx;
@@ -798,6 +799,7 @@ static void scrub_fixup_nodatasum(struct btrfs_work *work)
 
 	fixup = container_of(work, struct scrub_fixup_nodatasum, work);
 	sctx = fixup->sctx;
+	fs_info = fixup->root->fs_info;
 
 	path = btrfs_alloc_path();
 	if (!path) {
@@ -823,9 +825,8 @@ static void scrub_fixup_nodatasum(struct btrfs_work *work)
 	 * (once it's finished) and rewrite the failed sector if a good copy
 	 * can be found.
 	 */
-	ret = iterate_inodes_from_logical(fixup->logical, fixup->root->fs_info,
-						path, scrub_fixup_readpage,
-						fixup);
+	ret = iterate_inodes_from_logical(fixup->logical, fs_info, path,
+					  scrub_fixup_readpage, fixup);
 	if (ret < 0) {
 		uncorrectable = 1;
 		goto out;
@@ -843,9 +844,9 @@ out:
 		spin_lock(&sctx->stat_lock);
 		++sctx->stat.uncorrectable_errors;
 		spin_unlock(&sctx->stat_lock);
-		btrfs_dev_replace_stats_inc(&sctx->fs_info->dev_replace.
-						num_uncorrectable_read_errors);
-		btrfs_err_rl_in_rcu(sctx->fs_info,
+		btrfs_dev_replace_stats_inc(
+			&fs_info->dev_replace.num_uncorrectable_read_errors);
+		btrfs_err_rl_in_rcu(fs_info,
 		    "unable to fixup (nodatasum) error at logical %llu on dev %s",
 			fixup->logical, rcu_str_deref(fixup->dev->name));
 	}
@@ -1176,8 +1177,7 @@ nodatasum_case:
 			if (scrub_write_page_to_dev_replace(sblock_other,
 							    page_num) != 0) {
 				btrfs_dev_replace_stats_inc(
-					&sctx->fs_info->dev_replace.
-					num_write_errors);
+					&fs_info->dev_replace.num_write_errors);
 				success = 0;
 			}
 		} else if (sblock_other) {
@@ -1563,6 +1563,7 @@ static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
 {
 	struct scrub_page *page_bad = sblock_bad->pagev[page_num];
 	struct scrub_page *page_good = sblock_good->pagev[page_num];
+	struct btrfs_fs_info *fs_info = sblock_bad->sctx->fs_info;
 
 	BUG_ON(page_bad->page == NULL);
 	BUG_ON(page_good->page == NULL);
@@ -1572,7 +1573,7 @@ static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
 		int ret;
 
 		if (!page_bad->dev->bdev) {
-			btrfs_warn_rl(sblock_bad->sctx->fs_info,
+			btrfs_warn_rl(fs_info,
 				"scrub_repair_page_from_good_copy(bdev == NULL) is unexpected");
 			return -EIO;
 		}
@@ -1594,8 +1595,7 @@ static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
 			btrfs_dev_stat_inc_and_print(page_bad->dev,
 				BTRFS_DEV_STAT_WRITE_ERRS);
 			btrfs_dev_replace_stats_inc(
-				&sblock_bad->sctx->fs_info->
-				dev_replace.num_write_errors);
+				&fs_info->dev_replace.num_write_errors);
 			bio_put(bio);
 			return -EIO;
 		}
@@ -1607,6 +1607,7 @@ static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
 
 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock)
 {
+	struct btrfs_fs_info *fs_info = sblock->sctx->fs_info;
 	int page_num;
 
 	/*
@@ -1622,8 +1623,7 @@ static void scrub_write_block_to_dev_replace(struct scrub_block *sblock)
 		ret = scrub_write_page_to_dev_replace(sblock, page_num);
 		if (ret)
 			btrfs_dev_replace_stats_inc(
-				&sblock->sctx->fs_info->dev_replace.
-				num_write_errors);
+				&fs_info->dev_replace.num_write_errors);
 	}
 }
 
@@ -1857,8 +1857,7 @@ static int scrub_checksum_tree_block(struct scrub_block *sblock)
 {
 	struct scrub_ctx *sctx = sblock->sctx;
 	struct btrfs_header *h;
-	struct btrfs_root *root = sctx->fs_info->dev_root;
-	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_fs_info *fs_info = sctx->fs_info;
 	u8 calculated_csum[BTRFS_CSUM_SIZE];
 	u8 on_disk_csum[BTRFS_CSUM_SIZE];
 	struct page *page;
@@ -2138,6 +2137,7 @@ static void scrub_missing_raid56_worker(struct btrfs_work *work)
 {
 	struct scrub_block *sblock = container_of(work, struct scrub_block, work);
 	struct scrub_ctx *sctx = sblock->sctx;
+	struct btrfs_fs_info *fs_info = sctx->fs_info;
 	u64 logical;
 	struct btrfs_device *dev;
 
@@ -2151,14 +2151,14 @@ static void scrub_missing_raid56_worker(struct btrfs_work *work)
 		spin_lock(&sctx->stat_lock);
 		sctx->stat.read_errors++;
 		spin_unlock(&sctx->stat_lock);
-		btrfs_err_rl_in_rcu(sctx->fs_info,
+		btrfs_err_rl_in_rcu(fs_info,
 			"IO error rebuilding logical %llu for dev %s",
 			logical, rcu_str_deref(dev->name));
 	} else if (sblock->header_error || sblock->checksum_error) {
 		spin_lock(&sctx->stat_lock);
 		sctx->stat.uncorrectable_errors++;
 		spin_unlock(&sctx->stat_lock);
-		btrfs_err_rl_in_rcu(sctx->fs_info,
+		btrfs_err_rl_in_rcu(fs_info,
 			"failed to rebuild valid logical %llu for dev %s",
 			logical, rcu_str_deref(dev->name));
 	} else {
@@ -2749,6 +2749,7 @@ static void scrub_parity_bio_endio_worker(struct btrfs_work *work)
 static void scrub_parity_bio_endio(struct bio *bio)
 {
 	struct scrub_parity *sparity = (struct scrub_parity *)bio->bi_private;
+	struct btrfs_fs_info *fs_info = sparity->sctx->fs_info;
 
 	if (bio->bi_error)
 		bitmap_or(sparity->ebitmap, sparity->ebitmap, sparity->dbitmap,
@@ -2758,14 +2759,14 @@ static void scrub_parity_bio_endio(struct bio *bio)
 
 	btrfs_init_work(&sparity->work, btrfs_scrubparity_helper,
 			scrub_parity_bio_endio_worker, NULL, NULL);
-	btrfs_queue_work(sparity->sctx->fs_info->scrub_parity_workers,
-			 &sparity->work);
+	btrfs_queue_work(fs_info->scrub_parity_workers, &sparity->work);
 }
 
 static void scrub_parity_check_and_repair(struct scrub_parity *sparity)
 {
 	struct scrub_ctx *sctx = sparity->sctx;
-	struct btrfs_root *dev_root = sctx->fs_info->dev_root;
+	struct btrfs_fs_info *fs_info = sctx->fs_info;
+	struct btrfs_root *dev_root = fs_info->dev_root;
 	struct bio *bio;
 	struct btrfs_raid_bio *rbio;
 	struct scrub_page *spage;
@@ -2778,8 +2779,7 @@ static void scrub_parity_check_and_repair(struct scrub_parity *sparity)
 		goto out;
 
 	length = sparity->logic_end - sparity->logic_start;
-	ret = btrfs_map_sblock(sctx->fs_info, BTRFS_MAP_WRITE,
-			       sparity->logic_start,
+	ret = btrfs_map_sblock(fs_info, BTRFS_MAP_WRITE, sparity->logic_start,
 			       &length, &bbio, 0, 1);
 	if (ret || !bbio || !bbio->raid_map)
 		goto bbio_out;
@@ -2866,7 +2866,7 @@ static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx,
 	int extent_mirror_num;
 	int stop_loop = 0;
 
-	nsectors = div_u64(map->stripe_len, root->fs_info->sectorsize);
+	nsectors = div_u64(map->stripe_len, fs_info->sectorsize);
 	bitmap_len = scrub_calc_parity_bitmap_len(nsectors);
 	sparity = kzalloc(sizeof(struct scrub_parity) + 2 * bitmap_len,
 			  GFP_NOFS);
@@ -2937,7 +2937,7 @@ static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx,
 				goto next;
 
 			if (key.type == BTRFS_METADATA_ITEM_KEY)
-				bytes = root->fs_info->nodesize;
+				bytes = fs_info->nodesize;
 			else
 				bytes = key.offset;
 
@@ -3290,7 +3290,7 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
 				goto next;
 
 			if (key.type == BTRFS_METADATA_ITEM_KEY)
-				bytes = root->fs_info->nodesize;
+				bytes = fs_info->nodesize;
 			else
 				bytes = key.offset;
 
@@ -3497,8 +3497,8 @@ int scrub_enumerate_chunks(struct scrub_ctx *sctx,
 {
 	struct btrfs_dev_extent *dev_extent = NULL;
 	struct btrfs_path *path;
-	struct btrfs_root *root = sctx->fs_info->dev_root;
-	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_fs_info *fs_info = sctx->fs_info;
+	struct btrfs_root *root = fs_info->dev_root;
 	u64 length;
 	u64 chunk_offset;
 	int ret = 0;
@@ -3747,16 +3747,16 @@ static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
 	u64	bytenr;
 	u64	gen;
 	int	ret;
-	struct btrfs_root *root = sctx->fs_info->dev_root;
+	struct btrfs_fs_info *fs_info = sctx->fs_info;
 
-	if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state))
+	if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
 		return -EIO;
 
 	/* Seed devices of a new filesystem has their own generation. */
-	if (scrub_dev->fs_devices != root->fs_info->fs_devices)
+	if (scrub_dev->fs_devices != fs_info->fs_devices)
 		gen = scrub_dev->generation;
 	else
-		gen = root->fs_info->last_trans_committed;
+		gen = fs_info->last_trans_committed;
 
 	for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
 		bytenr = btrfs_sb_offset(i);
@@ -4052,16 +4052,17 @@ int btrfs_scrub_cancel_dev(struct btrfs_fs_info *fs_info,
 int btrfs_scrub_progress(struct btrfs_root *root, u64 devid,
 			 struct btrfs_scrub_progress *progress)
 {
+	struct btrfs_fs_info *fs_info = root->fs_info;
 	struct btrfs_device *dev;
 	struct scrub_ctx *sctx = NULL;
 
-	mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
-	dev = btrfs_find_device(root->fs_info, devid, NULL, NULL);
+	mutex_lock(&fs_info->fs_devices->device_list_mutex);
+	dev = btrfs_find_device(fs_info, devid, NULL, NULL);
 	if (dev)
 		sctx = dev->scrub_device;
 	if (sctx)
 		memcpy(progress, &sctx->stat, sizeof(*progress));
-	mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
+	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
 
 	return dev ? (sctx ? 0 : -ENOTCONN) : -ENODEV;
 }
@@ -4171,20 +4172,17 @@ static void copy_nocow_pages_worker(struct btrfs_work *work)
 	struct scrub_copy_nocow_ctx *nocow_ctx =
 		container_of(work, struct scrub_copy_nocow_ctx, work);
 	struct scrub_ctx *sctx = nocow_ctx->sctx;
+	struct btrfs_fs_info *fs_info = sctx->fs_info;
+	struct btrfs_root *root = fs_info->extent_root;
 	u64 logical = nocow_ctx->logical;
 	u64 len = nocow_ctx->len;
 	int mirror_num = nocow_ctx->mirror_num;
 	u64 physical_for_dev_replace = nocow_ctx->physical_for_dev_replace;
 	int ret;
 	struct btrfs_trans_handle *trans = NULL;
-	struct btrfs_fs_info *fs_info;
 	struct btrfs_path *path;
-	struct btrfs_root *root;
 	int not_written = 0;
 
-	fs_info = sctx->fs_info;
-	root = fs_info->extent_root;
-
 	path = btrfs_alloc_path();
 	if (!path) {
 		spin_lock(&sctx->stat_lock);