[PATCH RFC v2 for-6.8/block 16/18] ext4: use new helper to read sb block

[Yu Kuai]

From: Yu Kuai <yukuai3 at huawei.com>

Remove __ext4_sb_bread_gfp() and ext4_buffer_uptodate() that is defined
by ext4, and convert to use common helper __bread_gfp2() and
buffer_uptodate_or_error().

Signed-off-by: Yu Kuai <yukuai3 at huawei.com>
---
 fs/ext4/ext4.h    | 13 -------------
 fs/ext4/inode.c   |  8 ++++----
 fs/ext4/super.c   | 45 ++++++++++-----------------------------------
 fs/ext4/symlink.c |  2 +-
 4 files changed, 15 insertions(+), 53 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index a5d784872303..8377f6c5264f 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -3824,19 +3824,6 @@ extern const struct iomap_ops ext4_iomap_ops;
 extern const struct iomap_ops ext4_iomap_overwrite_ops;
 extern const struct iomap_ops ext4_iomap_report_ops;
 
-static inline int ext4_buffer_uptodate(struct buffer_head *bh)
-{
-	/*
-	 * If the buffer has the write error flag, we have failed
-	 * to write out data in the block.  In this  case, we don't
-	 * have to read the block because we may read the old data
-	 * successfully.
-	 */
-	if (buffer_write_io_error(bh))
-		set_buffer_uptodate(bh);
-	return buffer_uptodate(bh);
-}
-
 #endif	/* __KERNEL__ */
 
 #define EFSBADCRC	EBADMSG		/* Bad CRC detected */
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 61277f7f8722..efb0af6f02f7 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -887,7 +887,7 @@ struct buffer_head *ext4_bread(handle_t *handle, struct inode *inode,
 	bh = ext4_getblk(handle, inode, block, map_flags);
 	if (IS_ERR(bh))
 		return bh;
-	if (!bh || ext4_buffer_uptodate(bh))
+	if (!bh || buffer_uptodate_or_error(bh))
 		return bh;
 
 	ret = ext4_read_bh_lock(bh, REQ_META | REQ_PRIO, true);
@@ -915,7 +915,7 @@ int ext4_bread_batch(struct inode *inode, ext4_lblk_t block, int bh_count,
 
 	for (i = 0; i < bh_count; i++)
 		/* Note that NULL bhs[i] is valid because of holes. */
-		if (bhs[i] && !ext4_buffer_uptodate(bhs[i]))
+		if (bhs[i] && !buffer_uptodate_or_error(bhs[i]))
 			ext4_read_bh_lock(bhs[i], REQ_META | REQ_PRIO, false);
 
 	if (!wait)
@@ -4392,11 +4392,11 @@ static int __ext4_get_inode_loc(struct super_block *sb, unsigned long ino,
 	bh = sb_getblk(sb, block);
 	if (unlikely(!bh))
 		return -ENOMEM;
-	if (ext4_buffer_uptodate(bh))
+	if (buffer_uptodate_or_error(bh))
 		goto has_buffer;
 
 	lock_buffer(bh);
-	if (ext4_buffer_uptodate(bh)) {
+	if (buffer_uptodate_or_error(bh)) {
 		/* Someone brought it uptodate while we waited */
 		unlock_buffer(bh);
 		goto has_buffer;
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index c5fcf377ab1f..ae41204f52d4 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -180,7 +180,7 @@ void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
 {
 	BUG_ON(!buffer_locked(bh));
 
-	if (ext4_buffer_uptodate(bh)) {
+	if (buffer_uptodate_or_error(bh)) {
 		unlock_buffer(bh);
 		return;
 	}
@@ -191,7 +191,7 @@ int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags, bh_end_io_t *end_io
 {
 	BUG_ON(!buffer_locked(bh));
 
-	if (ext4_buffer_uptodate(bh)) {
+	if (buffer_uptodate_or_error(bh)) {
 		unlock_buffer(bh);
 		return 0;
 	}
@@ -214,49 +214,24 @@ int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait)
 	return ext4_read_bh(bh, op_flags, NULL);
 }
 
-/*
- * This works like __bread_gfp() except it uses ERR_PTR for error
- * returns.  Currently with sb_bread it's impossible to distinguish
- * between ENOMEM and EIO situations (since both result in a NULL
- * return.
- */
-static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
-					       sector_t block,
-					       blk_opf_t op_flags, gfp_t gfp)
-{
-	struct buffer_head *bh;
-	int ret;
-
-	bh = sb_getblk_gfp(sb, block, gfp);
-	if (bh == NULL)
-		return ERR_PTR(-ENOMEM);
-	if (ext4_buffer_uptodate(bh))
-		return bh;
-
-	ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
-	if (ret) {
-		put_bh(bh);
-		return ERR_PTR(ret);
-	}
-	return bh;
-}
-
 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 				   blk_opf_t op_flags)
 {
-	gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_inode->i_mapping,
-			~__GFP_FS) | __GFP_MOVABLE;
+	struct buffer_head *bh = __bread_gfp2(sb->s_bdev, block,
+					      sb->s_blocksize,
+					      REQ_META | op_flags,
+					      __GFP_MOVABLE);
 
-	return __ext4_sb_bread_gfp(sb, block, op_flags, gfp);
+	return bh ? bh : ERR_PTR(-EIO);
 }
 
 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 					    sector_t block)
 {
-	gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_inode->i_mapping,
-			~__GFP_FS);
+	struct buffer_head *bh = __bread_gfp2(sb->s_bdev, block,
+					      sb->s_blocksize, 0, 0);
 
-	return __ext4_sb_bread_gfp(sb, block, 0, gfp);
+	return bh ? bh : ERR_PTR(-EIO);
 }
 
 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
diff --git a/fs/ext4/symlink.c b/fs/ext4/symlink.c
index 75bf1f88843c..49e918221aac 100644
--- a/fs/ext4/symlink.c
+++ b/fs/ext4/symlink.c
@@ -94,7 +94,7 @@ static const char *ext4_get_link(struct dentry *dentry, struct inode *inode,
 		bh = ext4_getblk(NULL, inode, 0, EXT4_GET_BLOCKS_CACHED_NOWAIT);
 		if (IS_ERR(bh))
 			return ERR_CAST(bh);
-		if (!bh || !ext4_buffer_uptodate(bh))
+		if (!bh || !buffer_uptodate_or_error(bh))
 			return ERR_PTR(-ECHILD);
 	} else {
 		bh = ext4_bread(NULL, inode, 0, 0);
-- 
2.39.2