--- /dev/null 2007-03-13 19:15:28.862769062 +0100 +++ linux-2.6.21logfs/fs/logfs/Locking 2007-06-03 19:18:57.000000000 +0200 @@ -0,0 +1,45 @@ +Locks: + +s_victim_mutex +Protects victim inode for create, unlink, mkdir, rmdir, mknod, link, +symlink and one variant of rename. Only one victim inode may exist at +a time. In case of unclean unmount, victim inode has to be deleted +before next read-writable mount. + +s_rename_mutex +Protects victim dd for rename. Only one victim dd may exist at a +time. In case of unclean unmount, victim dd has to be deleted before +next read-writable mount. + +s_write_inode_mutex +Taken when writing an inode. Deleted inodes can be locked, preventing +further iget operations during writeout. Logfs may need to iget the +inode for garbage collection, so the inode in question needs to be +stored in the superblock and used directly without calling iget. + +s_log_sem +Used for allocating space in journal. + +s_r_sem +Protects the memory required for reads from the filesystem. + +s_w_sem +Protects the memory required for writes to the filesystem. + +s_ino_lock +Protects s_last_ino. + + +Lock order: +s_rename_mutex --> s_victim_mutex +s_rename_mutex --> s_write_inode_mutex +s_rename_mutex --> s_w_sem + +s_victim_mutex --> s_write_inode_mutex +s_victim_mutex --> s_w_sem +s_victim_mutex --> s_ino_lock + +s_write_inode_mutex --> s_w_sem + +s_w_sem --> s_log_sem +s_w_sem --> s_r_sem - To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
