[PATCH v2 8/11] erofs: support special inode

[Chao Yu]

From: Chao Yu <yuchao0 at huawei.com>

This patch adds to support special inode, such as block dev, char,
socket, pipe inode.

Reviewed-by: Gao Xiang <gaoxiang25 at huawei.com>
Signed-off-by: Chao Yu <yuchao0 at huawei.com>
---
v2: add default error handle case in read_inode().
 fs/erofs/inode.c    | 37 +++++++++++++++++++++++++++++++++++--
 fs/erofs/internal.h |  1 +
 2 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c
index 94e827b57a5b..e1a61c87680a 100644
--- a/fs/erofs/inode.c
+++ b/fs/erofs/inode.c
@@ -30,8 +30,18 @@ static int read_inode(struct inode *inode, void *data)
 		vi->inode_isize = sizeof(struct erofs_inode_v2);
 		vi->xattr_isize = ondisk_xattr_ibody_size(v2->i_xattr_icount);
 
-		vi->raw_blkaddr = le32_to_cpu(v2->i_u.raw_blkaddr);
 		inode->i_mode = le16_to_cpu(v2->i_mode);
+		if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+						S_ISLNK(inode->i_mode)) {
+			vi->raw_blkaddr = le32_to_cpu(v2->i_u.raw_blkaddr);
+		} else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
+			inode->i_rdev =
+				new_decode_dev(le32_to_cpu(v2->i_u.rdev));
+		} else if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
+			inode->i_rdev = 0;
+		} else {
+			return -EIO;
+		}
 
 		i_uid_write(inode, le32_to_cpu(v2->i_uid));
 		i_gid_write(inode, le32_to_cpu(v2->i_gid));
@@ -50,8 +60,18 @@ static int read_inode(struct inode *inode, void *data)
 		vi->inode_isize = sizeof(struct erofs_inode_v1);
 		vi->xattr_isize = ondisk_xattr_ibody_size(v1->i_xattr_icount);
 
-		vi->raw_blkaddr = le32_to_cpu(v1->i_u.raw_blkaddr);
 		inode->i_mode = le16_to_cpu(v1->i_mode);
+		if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
+						S_ISLNK(inode->i_mode)) {
+			vi->raw_blkaddr = le32_to_cpu(v1->i_u.raw_blkaddr);
+		} else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
+			inode->i_rdev =
+				new_decode_dev(le32_to_cpu(v1->i_u.rdev));
+		} else if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
+			inode->i_rdev = 0;
+		} else {
+			return -EIO;
+		}
 
 		i_uid_write(inode, le16_to_cpu(v1->i_uid));
 		i_gid_write(inode, le16_to_cpu(v1->i_gid));
@@ -168,6 +188,12 @@ int fill_inode(struct inode *inode, int isdir)
 				&page_symlink_inode_operations;
 #endif
 			inode_nohighmem(inode);
+		} else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
+			S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
+#ifdef CONFIG_EROFS_FS_XATTR
+			inode->i_op = &erofs_special_inode_operations;
+#endif
+			init_special_inode(inode, inode->i_mode, inode->i_rdev);
 		} else {
 			err = -EIO;
 			goto out_unlock;
@@ -244,6 +270,13 @@ const struct inode_operations erofs_symlink_xattr_iops = {
 	.listxattr = erofs_listxattr,
 #endif
 };
+
+const struct inode_operations erofs_special_inode_operations = {
+#if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 9, 0))
+		.listxattr = erofs_listxattr,
+#endif
+};
+
 #endif
 
 #if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 2, 0))
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 7670c2ed53d2..43620c07044d 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -364,6 +364,7 @@ extern const struct inode_operations simple_symlink_inode_operations;
 #ifdef CONFIG_EROFS_FS_XATTR
 extern const struct inode_operations erofs_symlink_xattr_iops;
 extern const struct inode_operations erofs_fast_symlink_xattr_iops;
+extern const struct inode_operations erofs_special_inode_operations;
 #endif
 
 static inline void set_inode_fast_symlink(struct inode *inode)
-- 
2.16.2.17.g38e79b1fd