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(ce3b0f8d5c2203301fc87f3aaaed73e5819e2a48: New helper - current_umask())
is removing the opts->fs_dmask, probably it's a cut-and-paste
miss or something.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
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* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (143 commits)
USB: xhci depends on PCI.
USB: xhci: Add Makefile, MAINTAINERS, and Kconfig entries.
USB: xhci: Respect critical sections.
USB: xHCI: Fix interrupt moderation.
USB: xhci: Remove packed attribute from structures.
usb; xhci: Fix TRB offset calculations.
USB: xhci: replace if-elseif-else with switch-case
USB: xhci: Make xhci-mem.c include linux/dmapool.h
USB: xhci: drop spinlock in xhci_urb_enqueue() error path.
USB: Change names of SuperSpeed ep companion descriptor structs.
USB: xhci: Avoid compiler reordering in Link TRB giveback.
USB: xhci: Clean up xhci_irq() function.
USB: xhci: Avoid global namespace pollution.
USB: xhci: Fix Link TRB handoff bit twiddling.
USB: xhci: Fix register write order.
USB: xhci: fix some compiler warnings in xhci.h
USB: xhci: fix lots of compiler warnings.
USB: xhci: use xhci_handle_event instead of handle_event
USB: xhci: URB cancellation support.
USB: xhci: Scatter gather list support for bulk transfers.
...
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* git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6:
fat: split fat_generic_ioctl
FAT: add 'errors' mount option
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This patch (as1239) updates the kernel's treatment of Unicode. The
character-set conversion routines are well behind the current state of
the Unicode specification: They don't recognize the existence of code
points beyond plane 0 or of surrogate pairs in the UTF-16 encoding.
The old wchar_t 16-bit type is retained because it's still used in
lots of places. This shouldn't cause any new problems; if a
conversion now results in an invalid 16-bit code then before it must
have yielded an undefined code.
Difficult-to-read names like "utf_mbstowcs" are replaced with more
transparent names like "utf8s_to_utf16s" and the ordering of the
parameters is rationalized (buffer lengths come immediate after the
pointers they refer to, and the inputs precede the outputs).
Fortunately the low-level conversion routines are used in only a few
places; the interfaces to the higher-level uni2char and char2uni
methods have been left unchanged.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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Add a ->sync_fs method for data integrity syncs.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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* mark directory data blocks as assoc. metadata
* add new inode to deal with FAT, mark FAT blocks as assoc. metadata of that
* now ->fsync() is trivial both for files and directories
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Push down lock_super into ->write_super instances and remove it from the
caller.
Following filesystem don't need ->s_lock in ->write_super and are skipped:
* bfs, nilfs2 - no other uses of s_lock and have internal locks in
->write_super
* ext2 - uses BKL in ext2_write_super and has internal calls without s_lock
* reiserfs - no other uses of s_lock as has reiserfs_write_lock (BKL) in
->write_super
* xfs - no other uses of s_lock and uses internal lock (buffer lock on
superblock buffer) to serialize ->write_super. Also xfs_fs_write_super
is superflous and will go away in the next merge window
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Move BKL into ->put_super from the only caller. A couple of
filesystems had trivial enough ->put_super (only kfree and NULLing of
s_fs_info + stuff in there) to not get any locking: coda, cramfs, efs,
hugetlbfs, omfs, qnx4, shmem, all others got the full treatment. Most
of them probably don't need it, but I'd rather sort that out individually.
Preferably after all the other BKL pushdowns in that area.
[AV: original used to move lock_super() down as well; these changes are
removed since we don't do lock_super() at all in generic_shutdown_super()
now]
[AV: fuse, btrfs and xfs are known to need no damn BKL, exempt]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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We just did a full fs writeout using sync_filesystem before, and if
that's not enough for the filesystem it can perform it's own writeout
in ->put_super, which many filesystems already do.
Move a call to foofs_write_super into every foofs_put_super for now to
guarantee identical behaviour until it's cleaned up by the individual
filesystem maintainers.
Exceptions:
- affs already has identical copy & pasted code at the beginning of
affs_put_super so no need to do it twice.
- xfs does the right thing without it and I have changes pending for
the xfs tree touching this are so I don't really need conflicts
here..
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Split up fat_generic_ioctl and add separate functions for the two
implemented ioctls.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
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On severe errors FAT remounts itself in read-only mode. Allow to
specify FAT fs desired behavior through 'errors' mount option:
panic, continue or remount read-only.
`mount -t [fat|vfat] -o errors=[panic,remount-ro,continue] \
<bdev> <mount point>`
This is analog to ext2 fs 'errors' mount option.
Signed-off-by: Denis Karpov <ext-denis.2.karpov@nokia.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
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Close bug #4754. Stop people getting into a situation where they can't
get their FAT filesystems to mount as they expect.
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
Remove two unneeded exports and make two symbols static in fs/mpage.c
Cleanup after commit 585d3bc06f4ca57f975a5a1f698f65a45ea66225
Trim includes of fdtable.h
Don't crap into descriptor table in binfmt_som
Trim includes in binfmt_elf
Don't mess with descriptor table in load_elf_binary()
Get rid of indirect include of fs_struct.h
New helper - current_umask()
check_unsafe_exec() doesn't care about signal handlers sharing
New locking/refcounting for fs_struct
Take fs_struct handling to new file (fs/fs_struct.c)
Get rid of bumping fs_struct refcount in pivot_root(2)
Kill unsharing fs_struct in __set_personality()
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Make fat return f_fsid info for statfs(2).
Signed-off-by: Coly Li <coly.li@suse.de>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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current->fs->umask is what most of fs_struct users are doing.
Put that into a helper function.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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On swapon() path, it has already i_mutex. So, this uses i_alloc_sem
instead of it.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reported-by: Laurent GUERBY <laurent@guerby.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
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* git://git.kernel.org/pub/scm/linux/kernel/git/hirofumi/fatfs-2.6:
fat: make sure to set d_ops in fat_get_parent
fat: fix duplicate addition of ->llseek handler
fat: drop negative dentry on rename() path
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Conflicts:
security/keys/internal.h
security/keys/process_keys.c
security/keys/request_key.c
Fixed conflicts above by using the non 'tsk' versions.
Signed-off-by: James Morris <jmorris@namei.org>
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Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.
Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().
Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: James Morris <jmorris@namei.org>
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fat_get_parent needs to setup the dentry operations, otherwise we might
lose them when the NFS server needs to reconnect out of cache inodes.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
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Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
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Drop the negative dentry on rename() path, in order to make sure to
use the case sensitive name which is specified by user if this is for
creation.
For it, this uses newly added LOOKUP_RENAME_TARGET like LOOKUP_CREATE.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
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blkcnt_t type depends on CONFIG_LSF. Use unsigned long long always for
printk(). But lazy to type it, so add "llu" and use it.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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i_pos is 64bits value, hence it's not atomic to update.
Important place is fat_write_inode() only, other places without lock
are just for printk().
This adds lock for "BITS_PER_LONG == 32" kernel.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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mmu_private is 64bits value, hence it's not atomic to update.
So, the access rule for mmu_private is we must hold ->i_mutex. But,
fat_get_block() path doesn't follow the rule on non-allocation path.
This fixes by using i_size instead if non-allocation path.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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fat_get_cluster() assumes the requested blocknr isn't truncated during
read. _fat_bmap() doesn't follow this rule.
This protects it by ->i_mutex.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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FAT has the ATTR_RO (read-only) attribute. But on Windows, the ATTR_RO
of the directory will be just ignored actually, and is used by only
applications as flag. E.g. it's setted for the customized folder by
Explorer.
http://msdn2.microsoft.com/en-us/library/aa969337.aspx
This adds "rodir" option. If user specified it, ATTR_RO is used as
read-only flag even if it's the directory. Otherwise, inode->i_mode
is not used to hold ATTR_RO (i.e. fat_mode_can_save_ro() returns 0).
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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If inode->i_mode doesn't have S_WUGO, current code assumes it means
ATTR_RO. However, if (~[ufd]mask & S_WUGO) == 0, inode->i_mode can't
hold S_WUGO. Therefore the updated directory entry will always have
ATTR_RO.
This adds fat_mode_can_hold_ro() to check it. And if inode->i_mode
can't hold, uses -i_attrs to hold ATTR_RO instead.
With this, we don't set ATTR_RO unless users change it via ioctl() if
(~[ufd]mask & S_WUGO) == 0.
And on FAT_IOCTL_GET_ATTRIBUTES path, this adds ->i_mutex to it for
not returning the partially updated attributes by FAT_IOCTL_SET_ATTRIBUTES
to userland.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This adds three helpers:
fat_make_attrs() - makes FAT attributes from inode.
fat_make_mode() - makes mode_t from FAT attributes.
fat_save_attrs() - saves FAT attributes to inode.
Then this replaces: MSDOS_MKMODE() by fat_make_mode(), fat_attr() by
fat_make_attrs(), ->i_attrs = attr & ATTR_UNUSED by fat_save_attrs().
And for root inode, those is used with ATTR_DIR instead of bogus
ATTR_NONE.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Use same style with vfat_lookup().
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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d_invalidate() for positive dentry doesn't work in some cases
(vfsmount, nfsd, and maybe others). shrink_dcache_parent() by
d_invalidate() is pointless for vfat usage at all.
So, this kills it, and intead of it uses d_move().
To save old behavior, this returns alias simply for directory (don't
change pwd, etc..). the directory lookup shouldn't be important for
performance.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- Add comments for handling dcache of vfat.
- Separate case-sensitive case and case-insensitive to
vfat_revalidate() and vfat_ci_revalidate().
vfat_revalidate() doesn't need to drop case-insensitive negative
dentry on creation path.
- Current code is missing to set ->d_revalidate to the negative dentry
created by unlink/etc..
This sets ->d_revalidate always, and returns 1 for positive
dentry. Now, we don't need to change ->d_op dynamically anymore,
so this just uses sb->s_root->d_op to set ->d_op.
- d_find_alias() may return DCACHE_DISCONNECTED dentry. It's not
the interesting dentry there. This checks it.
- Add missing LOOKUP_PARENT check. We don't need to drop the valid
negative dentry for (LOOKUP_CREATE | LOOKUP_PARENT) lookup.
- For consistent filename on creation path, this drops negative dentry
if we can't see intent.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Current vfat_lookup() creates negetive dentry blindly if vfat_find()
returned a error. It's wrong. If the error isn't -ENOENT, just return
error.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Use fat_detach() instead of opencoding it.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This fixes the missing update for bhs/nr_bhs in case the caller
accessed from block boundary to first block of boundary.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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fat_hash() is using the algorithm known as bad. Instead of it, this
uses hash_32(). The following is the summary of test.
old hash:
hash func (1000 times): 33489 cycles
total inodes in hash table: 70926
largest bucket contains: 696
smallest bucket contains: 54
new hash:
hash func (1000 times): 33129 cycles
total inodes in hash table: 70926
largest bucket contains: 315
smallest bucket contains: 236
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Coverity CID 2332 & 2333 RESOURCE_LEAK
In fat_search_long() if fat_parse_long() returns a -ve value we return
without first freeing unicode. This patch free's them on this error path.
The above was false positive on current tree, but this change is more
clean, so apply as cleanup.
[hirofumi@mail.parknet.co.jp: fix coding style]
Signed-off-by: Darren Jenkins <darrenrjenkins@gmail.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Since fat_dir_ioctl() was already fixed (i.e. called under ->i_mutex),
and __fat_readdir() doesn't take BKL anymore. So, BKL for ->llseek()
is pointless, and we have to use generic_file_llseek().
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This cleans date_dos2unix()/fat_date_unix2dos() up. New code should be
much more readable.
And this fixes those old functions. Those doesn't handle 2100
correctly. 2100 isn't leap year, but old one handles it as leap year.
Also, with this, centi sec is handled and is fixed.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This splits __KERNEL__ stuff in include/msdos_fs.h into fs/fat/fat.h.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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This just moves those files, but change link order from MSDOS, VFAT to
VFAT, MSDOS.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Nothing uses prepare_write or commit_write. Remove them from the tree
completely.
[akpm@linux-foundation.org: schedule simple_prepare_write() for unexporting]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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With this patch all directory fops instances that have a readdir
that doesn't take the BKL are switched to generic_file_llseek.
Signed-off-by: Christoph Hellwig <hch@lst.de>
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Switch all users of d_alloc_anon to d_obtain_alias.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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This is a much better version of a previous patch to make the parser
tables constant. Rather than changing the typedef, we put the "const" in
all the various places where its required, allowing the __initconst
exception for nfsroot which was the cause of the previous trouble.
This was posted for review some time ago and I believe its been in -mm
since then.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Alexander Viro <aviro@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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[hirofumi@mail.parknet.co.jp: discard _after_ checking for corrupt chains]
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
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There was another FAT BKL conversion deadlock reported by Bart
Trojanowski due to the BKL being used as a recursive lock by FAT, which
was missed because it only triggers with 'sync' (or 'dirsync') mounts.
The recursion worked for the BKL, but after the conversion to lock_super
(which uses a mutex), it just deadlocks.
Thanks to Bart for debugging this and testing the fix. The lock
debugging information from the original report:
=============================================
[ INFO: possible recursive locking detected ]
2.6.27-rc3-bisect-00448-ga7f5aaf #16
---------------------------------------------
mv/4020 is trying to acquire lock:
(&type->s_lock_key#9){--..}, at: [<c01a90fe>] lock_super+0x1e/0x20
but task is already holding lock:
(&type->s_lock_key#9){--..}, at: [<c01a90fe>] lock_super+0x1e/0x20
other info that might help us debug this:
3 locks held by mv/4020:
#0: (&sb->s_type->i_mutex_key#9/1){--..}, at: [<c01b2336>] do_unlinkat+0x66/0x140
#1: (&sb->s_type->i_mutex_key#9){--..}, at: [<c01b0954>] vfs_unlink+0x84/0x110
#2: (&type->s_lock_key#9){--..}, at: [<c01a90fe>] lock_super+0x1e/0x20
stack backtrace:
Pid: 4020, comm: mv Not tainted 2.6.27-rc3-bisect-00448-ga7f5aaf #16
[<c014e694>] validate_chain+0x984/0xea0
[<c0108d70>] ? native_sched_clock+0x0/0xf0
[<c014ee9c>] __lock_acquire+0x2ec/0x9b0
[<c014f5cf>] lock_acquire+0x6f/0x90
[<c01a90fe>] ? lock_super+0x1e/0x20
[<c044e5fd>] mutex_lock_nested+0xad/0x300
[<c01a90fe>] ? lock_super+0x1e/0x20
[<c01a90fe>] ? lock_super+0x1e/0x20
[<c01a90fe>] lock_super+0x1e/0x20
[<f8b3a700>] fat_write_inode+0x60/0x2b0 [fat]
[<c0450878>] ? _spin_unlock_irqrestore+0x48/0x80
[<f8b3a953>] ? fat_sync_inode+0x3/0x20 [fat]
[<f8b3a962>] fat_sync_inode+0x12/0x20 [fat]
[<f8b37c7e>] fat_remove_entries+0xbe/0x120 [fat]
[<f8b422ef>] vfat_unlink+0x5f/0x90 [vfat]
[<f8b42290>] ? vfat_unlink+0x0/0x90 [vfat]
[<c01b0968>] vfs_unlink+0x98/0x110
[<c01b2400>] do_unlinkat+0x130/0x140
[<c016a8f5>] ? audit_syscall_entry+0x105/0x150
[<c01b253b>] sys_unlinkat+0x3b/0x40
[<c01040d3>] sysenter_do_call+0x12/0x3f
=======================
where the deadlock is due to the nesting of lock_super from vfat_unlink
to fat_write_inode:
- do_unlinkat
- vfs_unlink
- vfat_unlink
* lock_super
- fat_remove_entries
- fat_sync_inode
- fat_write_inode
* lock_super
and the fix is to simply remove the use of lock_super() in fat_write_inode.
The lock_super() there had been just an automatic conversion of the
kernel lock to the superblock lock, but no locking was actually needed
there, since the code in fat_write_inode already protected all relevant
accesses with a spinlock (sbi->inode_hash_lock to be exact). The only
code inside the BKL (and thus the superblock lock) was accesses tp local
variables or calls to functions that have long been SMP-safe (i.e.
sb_bread, mark_buffe_dirty and brlese).
Bart reports:
"Looks good. I ran 10 parallel processes creating 1M files truncating
them, writing to them again and then deleting them. This patch fixes
the issue I ran into.
Signed-off-by: Bart Trojanowski <bart@jukie.net>"
Reported-and-tested-by: Bart Trojanowski <bart@jukie.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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