Currently, __dquot_transfer() acquires its own references of dquot structures that will be put into inode. But for OCFS2, this creates a lock inversion between dq_lock (waited on in dqget) and transaction start (started in ocfs2_setattr). Currently, deadlock is impossible because dq_lock is acquired only during dquot_acquire and dquot_release and we already hold a reference to dquot structures in ocfs2_setattr so neither of these functions can be called while we call dquot_transfer. But this is rather subtle and it is hard to teach lockdep about it. So provide __dquot_transfer function that can be passed dquot references directly. OCFS2 can then pass acquired dquot references directly to __dquot_transfer with proper locking. Signed-off-by: Jan Kara <jack@suse.cz> |
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| acpi | ||
| asm-generic | ||
| crypto | ||
| drm | ||
| keys | ||
| linux | ||
| math-emu | ||
| media | ||
| mtd | ||
| net | ||
| pcmcia | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| trace | ||
| video | ||
| xen | ||
| Kbuild | ||