erofs: use kmap_local_page() only for erofs_bread()

Convert all mapped erofs_bread() users to use kmap_local_page()
instead of kmap() or kmap_atomic().
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-and-tested-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20221018105313.4940-1-hsiangkao@linux.alibaba.comSigned-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>

fs/erofs/data.c

@@ -13,9 +13,7 @@
 void erofs_unmap_metabuf(struct erofs_buf *buf)
 {
 	if (buf->kmap_type == EROFS_KMAP)
-		kunmap(buf->page);
-	else if (buf->kmap_type == EROFS_KMAP_ATOMIC)
-		kunmap_atomic(buf->base);
+		kunmap_local(buf->base);
 	buf->base = NULL;
 	buf->kmap_type = EROFS_NO_KMAP;
 }
@@ -54,9 +52,7 @@ void *erofs_bread(struct erofs_buf *buf, struct inode *inode,
 	}
 	if (buf->kmap_type == EROFS_NO_KMAP) {
 		if (type == EROFS_KMAP)
-			buf->base = kmap(page);
-		else if (type == EROFS_KMAP_ATOMIC)
-			buf->base = kmap_atomic(page);
+			buf->base = kmap_local_page(page);
 		buf->kmap_type = type;
 	} else if (buf->kmap_type != type) {
 		DBG_BUGON(1);

fs/erofs/inode.c

@@ -268,6 +268,7 @@ static int erofs_fill_inode(struct inode *inode)
 	case S_IFDIR:
 		inode->i_op = &erofs_dir_iops;
 		inode->i_fop = &erofs_dir_fops;
+		inode_nohighmem(inode);
 		break;
 	case S_IFLNK:
 		err = erofs_fill_symlink(inode, kaddr, ofs);

fs/erofs/internal.h

@@ -255,8 +255,7 @@ static inline int erofs_wait_on_workgroup_freezed(struct erofs_workgroup *grp)
 
 enum erofs_kmap_type {
 	EROFS_NO_KMAP,		/* don't map the buffer */
-	EROFS_KMAP,		/* use kmap() to map the buffer */
-	EROFS_KMAP_ATOMIC,	/* use kmap_atomic() to map the buffer */
+	EROFS_KMAP,		/* use kmap_local_page() to map the buffer */
 };
 
 struct erofs_buf {

fs/erofs/xattr.c

@@ -148,7 +148,7 @@ static inline int xattr_iter_fixup(struct xattr_iter *it)
 
 	it->blkaddr += erofs_blknr(it->ofs);
 	it->kaddr = erofs_read_metabuf(&it->buf, it->sb, it->blkaddr,
-				       EROFS_KMAP_ATOMIC);
+				       EROFS_KMAP);
 	if (IS_ERR(it->kaddr))
 		return PTR_ERR(it->kaddr);
 	it->ofs = erofs_blkoff(it->ofs);
@@ -174,7 +174,7 @@ static int inline_xattr_iter_begin(struct xattr_iter *it,
 	it->ofs = erofs_blkoff(iloc(sbi, vi->nid) + inline_xattr_ofs);
 
 	it->kaddr = erofs_read_metabuf(&it->buf, inode->i_sb, it->blkaddr,
-				       EROFS_KMAP_ATOMIC);
+				       EROFS_KMAP);
 	if (IS_ERR(it->kaddr))
 		return PTR_ERR(it->kaddr);
 	return vi->xattr_isize - xattr_header_sz;
@@ -368,7 +368,7 @@ static int shared_getxattr(struct inode *inode, struct getxattr_iter *it)
 
 		it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]);
 		it->it.kaddr = erofs_read_metabuf(&it->it.buf, sb, blkaddr,
-						  EROFS_KMAP_ATOMIC);
+						  EROFS_KMAP);
 		if (IS_ERR(it->it.kaddr))
 			return PTR_ERR(it->it.kaddr);
 		it->it.blkaddr = blkaddr;
@@ -580,7 +580,7 @@ static int shared_listxattr(struct listxattr_iter *it)
 
 		it->it.ofs = xattrblock_offset(sbi, vi->xattr_shared_xattrs[i]);
 		it->it.kaddr = erofs_read_metabuf(&it->it.buf, sb, blkaddr,
-						  EROFS_KMAP_ATOMIC);
+						  EROFS_KMAP);
 		if (IS_ERR(it->it.kaddr))
 			return PTR_ERR(it->it.kaddr);
 		it->it.blkaddr = blkaddr;

fs/erofs/zmap.c

@@ -178,7 +178,7 @@ static int legacy_load_cluster_from_disk(struct z_erofs_maprecorder *m,
 	unsigned int advise, type;
 
 	m->kaddr = erofs_read_metabuf(&m->map->buf, inode->i_sb,
-				      erofs_blknr(pos), EROFS_KMAP_ATOMIC);
+				      erofs_blknr(pos), EROFS_KMAP);
 	if (IS_ERR(m->kaddr))
 		return PTR_ERR(m->kaddr);
 
@@ -416,7 +416,7 @@ static int compacted_load_cluster_from_disk(struct z_erofs_maprecorder *m,
 out:
 	pos += lcn * (1 << amortizedshift);
 	m->kaddr = erofs_read_metabuf(&m->map->buf, inode->i_sb,
-				      erofs_blknr(pos), EROFS_KMAP_ATOMIC);
+				      erofs_blknr(pos), EROFS_KMAP);
 	if (IS_ERR(m->kaddr))
 		return PTR_ERR(m->kaddr);
 	return unpack_compacted_index(m, amortizedshift, pos, lookahead);