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, 15 insertions, 13 deletions

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index e4a8c3a..750bae4 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -88,10 +88,11 @@ static int btrfs_decompress_bio(int type, struct page **pages_in,
 static inline int compressed_bio_size(struct btrfs_root *root,
 				      unsigned long disk_size)
 {
-	u16 csum_size = btrfs_super_csum_size(root->fs_info->super_copy);
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
 
 	return sizeof(struct compressed_bio) +
-		(DIV_ROUND_UP(disk_size, root->fs_info->sectorsize)) * csum_size;
+		(DIV_ROUND_UP(disk_size, fs_info->sectorsize)) * csum_size;
 }
 
 static struct bio *compressed_bio_alloc(struct block_device *bdev,
@@ -328,6 +329,7 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 				 struct page **compressed_pages,
 				 unsigned long nr_pages)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct bio *bio = NULL;
 	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct compressed_bio *cb;
@@ -355,7 +357,7 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 	cb->orig_bio = NULL;
 	cb->nr_pages = nr_pages;
 
-	bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
+	bdev = fs_info->fs_devices->latest_bdev;
 
 	bio = compressed_bio_alloc(bdev, first_byte, GFP_NOFS);
 	if (!bio) {
@@ -391,8 +393,8 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 			 * freed before we're done setting it up
 			 */
 			atomic_inc(&cb->pending_bios);
-			ret = btrfs_bio_wq_end_io(root->fs_info, bio,
-					BTRFS_WQ_ENDIO_DATA);
+			ret = btrfs_bio_wq_end_io(fs_info, bio,
+						  BTRFS_WQ_ENDIO_DATA);
 			BUG_ON(ret); /* -ENOMEM */
 
 			if (!skip_sum) {
@@ -417,7 +419,7 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 			bio_add_page(bio, page, PAGE_SIZE, 0);
 		}
 		if (bytes_left < PAGE_SIZE) {
-			btrfs_info(BTRFS_I(inode)->root->fs_info,
+			btrfs_info(fs_info,
 					"bytes left %lu compress len %lu nr %lu",
 			       bytes_left, cb->compressed_len, cb->nr_pages);
 		}
@@ -427,7 +429,7 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start,
 	}
 	bio_get(bio);
 
-	ret = btrfs_bio_wq_end_io(root->fs_info, bio, BTRFS_WQ_ENDIO_DATA);
+	ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA);
 	BUG_ON(ret); /* -ENOMEM */
 
 	if (!skip_sum) {
@@ -575,6 +577,7 @@ next:
 int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 				 int mirror_num, unsigned long bio_flags)
 {
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct extent_io_tree *tree;
 	struct extent_map_tree *em_tree;
 	struct compressed_bio *cb;
@@ -634,7 +637,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	if (!cb->compressed_pages)
 		goto fail1;
 
-	bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
+	bdev = fs_info->fs_devices->latest_bdev;
 
 	for (pg_index = 0; pg_index < nr_pages; pg_index++) {
 		cb->compressed_pages[pg_index] = alloc_page(GFP_NOFS |
@@ -678,8 +681,8 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 		    PAGE_SIZE) {
 			bio_get(comp_bio);
 
-			ret = btrfs_bio_wq_end_io(root->fs_info, comp_bio,
-					BTRFS_WQ_ENDIO_DATA);
+			ret = btrfs_bio_wq_end_io(fs_info, comp_bio,
+						  BTRFS_WQ_ENDIO_DATA);
 			BUG_ON(ret); /* -ENOMEM */
 
 			/*
@@ -696,7 +699,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 				BUG_ON(ret); /* -ENOMEM */
 			}
 			sums += DIV_ROUND_UP(comp_bio->bi_iter.bi_size,
-					     root->fs_info->sectorsize);
+					     fs_info->sectorsize);
 
 			ret = btrfs_map_bio(root, comp_bio, mirror_num, 0);
 			if (ret) {
@@ -719,8 +722,7 @@ int btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
 	}
 	bio_get(comp_bio);
 
-	ret = btrfs_bio_wq_end_io(root->fs_info, comp_bio,
-			BTRFS_WQ_ENDIO_DATA);
+	ret = btrfs_bio_wq_end_io(fs_info, comp_bio, BTRFS_WQ_ENDIO_DATA);
 	BUG_ON(ret); /* -ENOMEM */
 
 	if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {