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@@ -144,8 +144,8 @@ prototypes:
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void (*kill_sb) (struct super_block *);
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void (*kill_sb) (struct super_block *);
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locking rules:
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locking rules:
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may block BKL
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may block BKL
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-get_sb yes yes
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-kill_sb yes yes
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+get_sb yes no
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+kill_sb yes no
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->get_sb() returns error or 0 with locked superblock attached to the vfsmount
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->get_sb() returns error or 0 with locked superblock attached to the vfsmount
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(exclusive on ->s_umount).
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(exclusive on ->s_umount).
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@@ -409,12 +409,12 @@ ioctl: yes (see below)
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unlocked_ioctl: no (see below)
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unlocked_ioctl: no (see below)
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compat_ioctl: no
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compat_ioctl: no
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mmap: no
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mmap: no
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-open: maybe (see below)
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+open: no
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flush: no
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flush: no
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release: no
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release: no
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fsync: no (see below)
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fsync: no (see below)
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aio_fsync: no
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aio_fsync: no
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-fasync: yes (see below)
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+fasync: no
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lock: yes
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lock: yes
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readv: no
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readv: no
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writev: no
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writev: no
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@@ -431,13 +431,6 @@ For many filesystems, it is probably safe to acquire the inode
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semaphore. Note some filesystems (i.e. remote ones) provide no
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semaphore. Note some filesystems (i.e. remote ones) provide no
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protection for i_size so you will need to use the BKL.
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protection for i_size so you will need to use the BKL.
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-->open() locking is in-transit: big lock partially moved into the methods.
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-The only exception is ->open() in the instances of file_operations that never
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-end up in ->i_fop/->proc_fops, i.e. ones that belong to character devices
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-(chrdev_open() takes lock before replacing ->f_op and calling the secondary
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-method. As soon as we fix the handling of module reference counters all
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-instances of ->open() will be called without the BKL.
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-
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Note: ext2_release() was *the* source of contention on fs-intensive
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Note: ext2_release() was *the* source of contention on fs-intensive
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loads and dropping BKL on ->release() helps to get rid of that (we still
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loads and dropping BKL on ->release() helps to get rid of that (we still
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grab BKL for cases when we close a file that had been opened r/w, but that
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grab BKL for cases when we close a file that had been opened r/w, but that
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Christoph Hellwig