[PATCH 03/32] IGET: Introduce a function to register iget failure [try #2]

David Howells
2007-10-04T15:57:28Z

Introduce a function to register failure in an inode construction path. This
includes marking the inode under construction as bad, unlocking it and
releasing it.

Signed-off-by: David Howells <dhowells@redhat.com>
---

Documentation/filesystems/porting | 18 +++++++++++++-----
fs/bad_inode.c | 14 ++++++++++++++
include/linux/fs.h | 1 +
3 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index dac45c9..3b0fb22 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -184,11 +184,19 @@ just takes the superblock and inode number as arguments and does the
test and set for you.

e.g.
- inode = iget_locked(sb, ino);
- if (inode->i_state & I_NEW) {
- read_inode_from_disk(inode);
- unlock_new_inode(inode);
- }
+ inode = iget_locked(sb, ino);
+ if (inode->i_state & I_NEW) {
+ err = read_inode_from_disk(inode);
+ if (err < 0) {
+ iget_failed(inode);
+ return err;
+ }
+ unlock_new_inode(inode);
+ }
+
+Note that if the process of setting up a new inode fails, then iget_failed()
+should be called on the inode to render it dead, and an appropriate error
+should be passed back to the caller.

---
[recommended]
diff --git a/fs/bad_inode.c b/fs/bad_inode.c
index 521ff7c..f1c2ea8 100644
--- a/fs/bad_inode.c
+++ b/fs/bad_inode.c
@@ -359,3 +359,17 @@ int is_bad_inode(struct inode *inode)
}

EXPORT_SYMBOL(is_bad_inode);
+
+/**
+ * iget_failed - Mark an under-construction inode as dead and release it
+ * @inode: The inode to discard
+ *
+ * Mark an under-construction inode as dead and release it.
+ */
+void iget_failed(struct inode *inode)
+{
+ make_bad_inode(inode);
+ unlock_new_inode(inode);
+ iput(inode);
+}
+EXPORT_SYMBOL(iget_failed);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 16421f6..c24d433 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1631,6 +1631,7 @@ static inline struct inode *iget(struct super_block *sb, unsigned long ino)
}

extern void __iget(struct inode * inode);
+extern void iget_failed(struct inode *);
extern void clear_inode(struct inode *);
extern void destroy_inode(struct inode *);
extern struct inode *new_inode(struct super_block *);