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>
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>
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>
- 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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
FAT has to handle the newly introduced ATTR_TIMES_SET for allow_utime
option.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The FAT_IOCTL_SET_ATTRIBUTES ioctl() calls notify_change() to change
the file mode before changing the inode attributes. Replace with
explicit calls to security_inode_setattr(), fat_setattr() and
fsnotify_change().
This is equivalent to the original. The reason it is needed, is that
later in the series we move the immutable check into notify_change().
That would break the FAT_IOCTL_SET_ATTRIBUTES ioctl, as it needs to
perform the mode change regardless of the immutability of the file.
[Fix error if fat is built as a module. Thanks to OGAWA Hirofumi for
noticing.]
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Kmem cache passed to constructor is only needed for constructors that are
themselves multiplexeres. Nobody uses this "feature", nor does anybody uses
passed kmem cache in non-trivial way, so pass only pointer to object.
Non-trivial places are:
arch/powerpc/mm/init_64.c
arch/powerpc/mm/hugetlbpage.c
This is flag day, yes.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Pekka Enberg <penberg@cs.helsinki.fi>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Jon Tollefson <kniht@linux.vnet.ibm.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Matt Mackall <mpm@selenic.com>
[akpm@linux-foundation.org: fix arch/powerpc/mm/hugetlbpage.c]
[akpm@linux-foundation.org: fix mm/slab.c]
[akpm@linux-foundation.org: fix ubifs]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Provide a new mount option ("tz=UTC") for DOS (vfat/msdos) filesystems,
allowing timestamps to be in coordinated universal time (UTC) rather than
local time in applications where doing this is advantageous.
In particular, portable devices that use fat/vfat (such as digital
cameras) can benefit from using UTC in their internal clocks, thus
avoiding daylight saving time errors and general time ambiguity issues.
The user of the device does not have to worry about changing the time when
moving from place or when daylight saving changes.
The new mount option, when set, disables the counter-adjustment that Linux
currently makes to FAT timestamp info in anticipation of the normal
userspace time zone correction. When used in this new mode, all daylight
saving time and time zone handling is done in userspace as is normal for
many other filesystems (like ext3). The default mode, which remains
unchanged, is still appropriate when mounting volumes written in Windows
(because of its use of local time).
I originally based this patch on one submitted last year by Paul Collins,
but I updated it to work with current source and changed variable/option
naming. Ogawa Hirofumi (who maintains these filesystems) and I discussed
this patch at length on lkml, and he suggested using the option name in
the attached version of the patch. Barry Bouwsma pointed out a good
addition to the patch as well.
Signed-off-by: Joe Peterson <joe@skyrush.com>
Signed-off-by: Paul Collins <paul@ondioline.org>
Acked-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Barry Bouwsma <free_beer_for_all@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This removes unnecessary parsing for directory entries.
If short_only, we don't need to parse longname. And if !both and it found
the longname, we don't need shortname.
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>
This uses uses stack for shortname, and uses __getname() for longname in
fat_search_long() and __fat_readdir(). By this, it removes unneeded
__getname() for shortname.
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>
This is no logic changes, just cleans fs/fat/dir.c up.
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>
struct __fat_dirent is what was formerly the kernel struct dirent (that
was different from the userspace struct dirent).
Converting all fat users to struct __fat_dirent will allow us to get rid
of the conflicting struct dirent definition.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
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>
Current parse_options() exits too early. We need to run the code of
bottom in this function even if users doesn't specify options.
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>
The FAT BKL removal patch can cause deadlocks. It turns out that the new
lock_super() calls are unneeded, remove them (as directed by Linus).
Reported-by: "Tony Luck" <tony.luck@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This replaces the use of the BKL in the FAT family of filesystems with the
existing superblock lock instead.
The code already appears to do mostly proper locking with its own private
spinlocks (and mutexes), but while the BKL could possibly have been
dropped entirely, converting it to use the superblock lock (which is just
a regular mutex) is the conservative thing to do.
As a per-filesystem mutex, it not only won't have any of the possible
latency issues related to the BKL, but the lock is obviously private to
the particular filesystem instance and will thus not cause problems for
entirely unrelated users like the BKL can.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
New chmod() allows only acceptable permission, and if not acceptable, it
returns -EPERM. Old one allows even if it can't store permission to on
disk inode. But it seems too strict for users.
E.g. https://bugzilla.redhat.com/show_bug.cgi?id=449080: With new one,
rsync couldn't create the temporary file.
So, this patch allows like old one, but now it doesn't change the
permission if it can't store, and it returns 0.
Also, this patch fixes missing check.
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>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Annoying gcc warning:
fs/fat/inode.c: In function 'fat_fill_super':
fs/fat/inode.c:1222: warning: comparison is always false due to limited range of data type
Change it to compare with 4K instead of PAGE_CACHE_SIZE, as suggested
by OGAWA-san.
[FAT spec says: logical_sector_size should be 512, 1024, 2048 4096]
So, at least for now, we limit it to 4096.
Signed-off-by: Olof Johansson <olof@lixom.net>
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>
The on-disk media specification field in FAT is only 8-bits, so testing for
<=0xff is pointless, and can generate a "comparison is always true due to
limited range of data type" warning.
While we're there, convert FAT_VALID_MEDIA() into a C function - the present
implementation is buggy: it generates either one or two references to its
argument.
Cc: Frank Seidel <fseidel@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>
__getname() is faster than __get_free_page(). 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>
This patch fix the problem that the buffer allocated for convert of unicode to
utf8 in fat/dir.c is too small.
And cannot handle filename with 255 asian characters when mounted with utf8
options.
Also it fix the filename length limitation checking in vfat/namei.c that the
filename length should be checked against the number of converted unicode
characters.
Not the length before NLS/UTF8 converted.
Signed-off-by: Keith Mok <ek9852@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>
Currently, free_clusters is not updated until it is trusted, because
Windows doesn't update it correctly.
But if user is using FAT driver of Linux, it updates free_clusters
correctly. Instead, this updates it even if it's untrusted, so if
free_clustes is correct, now keep correct value.
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>
Normally utime(2) checks current process is owner of the file, or it
has CAP_FOWNER capability. But FAT filesystem doesn't have uid/gid as
on disk info, so normal check is too unflexible.
With this option you can relax 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>
Fix fat_setattr() on the case of showexec option. If user specified
showexec option, inode->i_mode may not have S_IXUGO. This just use
inode->i_mode to fix it.
And with this patch, we don't allow chmod() on memory inode, it's just
bad behaviour. IOW, we allow changing S_IWUGO only which can be stored
to disk.
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>
FAT doesn't need to check bad inode anymore.
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>
Some ioctl()s can cause writes to the filesystem. Take these, and make them
use mnt_want/drop_write() instead.
[AV: updated]
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Stop the FAT filesystem from using iget() and read_inode(). Replace the call
to iget() with a call to ilookup().
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This makes sure printk format strings contain no more than a single line.
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
[the message was tweaked.]
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>
Prohibit mode changes in non-quiet mode that cannot be stored reliably with
the on-disk format.
Suppose a vfat filesystem is mounted with umask=0 and [not-quiet]. Then
all files will have mode 0777. Trying to change the owner will fail,
because fat does not know about owners or groups. chmod 0770, on the other
hand, will succeed, even though fat does not know about the permission
triplet [user/group/other].
So this patch changes fat's not-quiet behavior so that only UNIX modes are
accepted that can be mapped lossless between the fat disk format and the
local system. There is only one attribute, and that is the readonly
attribute, which is mapped to the UNIX write permission bit(s). chmod 0555
is therefore valid (taking away the +w bits <=> setting the readonly
attribute). Since chmod 0775 and chmod 0755 is an ambiguous case as to
whether to set or clear the readonly bit, these modes are also denied.
In quiet mode, chmod and chown will continue to "succeed" as they did
before, meaning that a subsequent stat() will temporarily return the new
mode as long as the inode is not reread from disk, and chown will silently
do nothing, not even return the new uid/gid in stat().
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Cc: 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>
OGAWA Hirofumi