Since 3.14 we had copy_tree() get the shadowing wrong - if we had one
vfsmount shadowing another (i.e. if A is a slave of B, C is mounted
on A/foo, then D got mounted on B/foo creating D' on A/foo shadowed
by C), copy_tree() of A would make a copy of D' shadow the the copy of
C, not the other way around.
It's easy to fix, fortunately - just make sure that mount follows
the one that shadows it in mnt_child as well as in mnt_hash, and when
copy_tree() decides to attach a new mount, check if the last child
it has added to the same parent should be shadowing the new one.
And if it should, just use the same logics commit_tree() has - put the
new mount into the hash and children lists right after the one that
should shadow it.
Cc: stable@vger.kernel.org [3.14 and later]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Commit 743162013d ("sched: Remove proliferation of wait_on_bit() action
functions") has removed the call to cifs_oplock_break_wait, making this
function unused; remove it.
This fixes the following compilation warning:
fs/cifs/misc.c:578:1: warning: ‘cifs_oplock_break_wait’ defined but not used [-Wunused-function]
Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net>
Cc: Steve French <sfrench@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
This reverts commits 344470cac4 and e813244072.
It turns out that the exact path in the symlink matters, if for somewhat
unfortunate reasons: some apparmor configurations don't allow dhclient
access to the per-thread /proc files. As reported by Jörg Otte:
audit: type=1400 audit(1407684227.003:28): apparmor="DENIED"
operation="open" profile="/sbin/dhclient"
name="/proc/1540/task/1540/net/dev" pid=1540 comm="dhclient"
requested_mask="r" denied_mask="r" fsuid=0 ouid=0
so we had better revert this for now. We might be able to work around
this in practice by only using the per-thread symlinks if the thread
isn't the thread group leader, and if the namespaces differ between
threads (which basically never happens).
We'll see. In the meantime, the revert was made to be intentionally easy.
Reported-by: Jörg Otte <jrg.otte@gmail.com>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull namespace updates from Eric Biederman:
"This is a bunch of small changes built against 3.16-rc6. The most
significant change for users is the first patch which makes setns
drmatically faster by removing unneded rcu handling.
The next chunk of changes are so that "mount -o remount,.." will not
allow the user namespace root to drop flags on a mount set by the
system wide root. Aks this forces read-only mounts to stay read-only,
no-dev mounts to stay no-dev, no-suid mounts to stay no-suid, no-exec
mounts to stay no exec and it prevents unprivileged users from messing
with a mounts atime settings. I have included my test case as the
last patch in this series so people performing backports can verify
this change works correctly.
The next change fixes a bug in NFS that was discovered while auditing
nsproxy users for the first optimization. Today you can oops the
kernel by reading /proc/fs/nfsfs/{servers,volumes} if you are clever
with pid namespaces. I rebased and fixed the build of the
!CONFIG_NFS_FS case yesterday when a build bot caught my typo. Given
that no one to my knowledge bases anything on my tree fixing the typo
in place seems more responsible that requiring a typo-fix to be
backported as well.
The last change is a small semantic cleanup introducing
/proc/thread-self and pointing /proc/mounts and /proc/net at it. This
prevents several kinds of problemantic corner cases. It is a
user-visible change so it has a minute chance of causing regressions
so the change to /proc/mounts and /proc/net are individual one line
commits that can be trivially reverted. Unfortunately I lost and
could not find the email of the original reporter so he is not
credited. From at least one perspective this change to /proc/net is a
refgression fix to allow pthread /proc/net uses that were broken by
the introduction of the network namespace"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
proc: Point /proc/mounts at /proc/thread-self/mounts instead of /proc/self/mounts
proc: Point /proc/net at /proc/thread-self/net instead of /proc/self/net
proc: Implement /proc/thread-self to point at the directory of the current thread
proc: Have net show up under /proc/<tgid>/task/<tid>
NFS: Fix /proc/fs/nfsfs/servers and /proc/fs/nfsfs/volumes
mnt: Add tests for unprivileged remount cases that have found to be faulty
mnt: Change the default remount atime from relatime to the existing value
mnt: Correct permission checks in do_remount
mnt: Move the test for MNT_LOCK_READONLY from change_mount_flags into do_remount
mnt: Only change user settable mount flags in remount
namespaces: Use task_lock and not rcu to protect nsproxy
Pull nfsd updates from Bruce Fields:
"This includes a major rewrite of the NFSv4 state code, which has
always depended on a single mutex. As an example, open creates are no
longer serialized, fixing a performance regression on NFSv3->NFSv4
upgrades. Thanks to Jeff, Trond, and Benny, and to Christoph for
review.
Also some RDMA fixes from Chuck Lever and Steve Wise, and
miscellaneous fixes from Kinglong Mee and others"
* 'for-3.17' of git://linux-nfs.org/~bfields/linux: (167 commits)
svcrdma: remove rdma_create_qp() failure recovery logic
nfsd: add some comments to the nfsd4 object definitions
nfsd: remove the client_mutex and the nfs4_lock/unlock_state wrappers
nfsd: remove nfs4_lock_state: nfs4_state_shutdown_net
nfsd: remove nfs4_lock_state: nfs4_laundromat
nfsd: Remove nfs4_lock_state(): reclaim_complete()
nfsd: Remove nfs4_lock_state(): setclientid, setclientid_confirm, renew
nfsd: Remove nfs4_lock_state(): exchange_id, create/destroy_session()
nfsd: Remove nfs4_lock_state(): nfsd4_open and nfsd4_open_confirm
nfsd: Remove nfs4_lock_state(): nfsd4_delegreturn()
nfsd: Remove nfs4_lock_state(): nfsd4_open_downgrade + nfsd4_close
nfsd: Remove nfs4_lock_state(): nfsd4_lock/locku/lockt()
nfsd: Remove nfs4_lock_state(): nfsd4_release_lockowner
nfsd: Remove nfs4_lock_state(): nfsd4_test_stateid/nfsd4_free_stateid
nfsd: Remove nfs4_lock_state(): nfs4_preprocess_stateid_op()
nfsd: remove old fault injection infrastructure
nfsd: add more granular locking to *_delegations fault injectors
nfsd: add more granular locking to forget_openowners fault injector
nfsd: add more granular locking to forget_locks fault injector
nfsd: add a list_head arg to nfsd_foreach_client_lock
...
Pull CIFS updates from Steve French:
"The most visible change in this set is the additional of multi-credit
support for SMB2/SMB3 which dramatically improves the large file i/o
performance for these dialects and significantly increases the maximum
i/o size used on the wire for SMB2/SMB3.
Also reconnection behavior after network failure is improved"
* 'for-next' of git://git.samba.org/sfrench/cifs-2.6: (35 commits)
Add worker function to set allocation size
[CIFS] Fix incorrect hex vs. decimal in some debug print statements
update CIFS TODO list
Add Pavel to contributor list in cifs AUTHORS file
Update cifs version
CIFS: Fix STATUS_CANNOT_DELETE error mapping for SMB2
CIFS: Optimize readpages in a short read case on reconnects
CIFS: Optimize cifs_user_read() in a short read case on reconnects
CIFS: Improve indentation in cifs_user_read()
CIFS: Fix possible buffer corruption in cifs_user_read()
CIFS: Count got bytes in read_into_pages()
CIFS: Use separate var for the number of bytes got in async read
CIFS: Indicate reconnect with ECONNABORTED error code
CIFS: Use multicredits for SMB 2.1/3 reads
CIFS: Fix rsize usage for sync read
CIFS: Fix rsize usage in user read
CIFS: Separate page reading from user read
CIFS: Fix rsize usage in readpages
CIFS: Separate page search from readpages
CIFS: Use multicredits for SMB 2.1/3 writes
...
AMD-compatible CFI driver:
- Support OTP programming for Micron M29EW family
- Increase buffer write timeout, according to detected flash parameter info
NAND
- Add helpers for retrieving ONFI timing modes
- GPMI: provide option to disable bad block marker swapping (required for
Ka-On electronics platforms)
SPI NOR
- EON EN25QH128 support
- Support new Flag Status Register (FSR) on a few Micron flash
Common
- New sysfs entries for bad block and ECC stats
And a few miscellaneous refactorings, cleanups, and driver improvements
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Merge tag 'for-linus-20140808' of git://git.infradead.org/linux-mtd
Pull MTD updates from Brian Norris:
"AMD-compatible CFI driver:
- Support OTP programming for Micron M29EW family
- Increase buffer write timeout, according to detected flash
parameter info
NAND
- Add helpers for retrieving ONFI timing modes
- GPMI: provide option to disable bad block marker swapping (required
for Ka-On electronics platforms)
SPI NOR
- EON EN25QH128 support
- Support new Flag Status Register (FSR) on a few Micron flash
Common
- New sysfs entries for bad block and ECC stats
And a few miscellaneous refactorings, cleanups, and driver
improvements"
* tag 'for-linus-20140808' of git://git.infradead.org/linux-mtd: (31 commits)
mtd: gpmi: make blockmark swapping optional
mtd: gpmi: remove line breaks from error messages and improve wording
mtd: gpmi: remove useless (void *) type casts and spaces between type casts and variables
mtd: atmel_nand: NFC: support multiple interrupt handling
mtd: atmel_nand: implement the nfc_device_ready() by checking the R/B bit
mtd: atmel_nand: add NFC status error check
mtd: atmel_nand: make ecc parameters same as definition
mtd: nand: add ONFI timing mode to nand_timings converter
mtd: nand: define struct nand_timings
mtd: cfi_cmdset_0002: fix do_write_buffer() timeout error
mtd: denali: use 8 bytes for READID command
mtd/ftl: fix the double free of the buffers allocated in build_maps()
mtd: phram: Fix whitespace issues
mtd: spi-nor: add support for EON EN25QH128
mtd: cfi_cmdset_0002: Add support for locking OTP memory
mtd: cfi_cmdset_0002: Add support for writing OTP memory
mtd: cfi_cmdset_0002: Invalidate cache after entering/exiting OTP memory
mtd: cfi_cmdset_0002: Add support for reading OTP
mtd: spi-nor: add support for flag status register on Micron chips
mtd: Account for BBT blocks when a partition is being allocated
...
If two processes share a common memory region, they usually want some
guarantees to allow safe access. This often includes:
- one side cannot overwrite data while the other reads it
- one side cannot shrink the buffer while the other accesses it
- one side cannot grow the buffer beyond previously set boundaries
If there is a trust-relationship between both parties, there is no need
for policy enforcement. However, if there's no trust relationship (eg.,
for general-purpose IPC) sharing memory-regions is highly fragile and
often not possible without local copies. Look at the following two
use-cases:
1) A graphics client wants to share its rendering-buffer with a
graphics-server. The memory-region is allocated by the client for
read/write access and a second FD is passed to the server. While
scanning out from the memory region, the server has no guarantee that
the client doesn't shrink the buffer at any time, requiring rather
cumbersome SIGBUS handling.
2) A process wants to perform an RPC on another process. To avoid huge
bandwidth consumption, zero-copy is preferred. After a message is
assembled in-memory and a FD is passed to the remote side, both sides
want to be sure that neither modifies this shared copy, anymore. The
source may have put sensible data into the message without a separate
copy and the target may want to parse the message inline, to avoid a
local copy.
While SIGBUS handling, POSIX mandatory locking and MAP_DENYWRITE provide
ways to achieve most of this, the first one is unproportionally ugly to
use in libraries and the latter two are broken/racy or even disabled due
to denial of service attacks.
This patch introduces the concept of SEALING. If you seal a file, a
specific set of operations is blocked on that file forever. Unlike locks,
seals can only be set, never removed. Hence, once you verified a specific
set of seals is set, you're guaranteed that no-one can perform the blocked
operations on this file, anymore.
An initial set of SEALS is introduced by this patch:
- SHRINK: If SEAL_SHRINK is set, the file in question cannot be reduced
in size. This affects ftruncate() and open(O_TRUNC).
- GROW: If SEAL_GROW is set, the file in question cannot be increased
in size. This affects ftruncate(), fallocate() and write().
- WRITE: If SEAL_WRITE is set, no write operations (besides resizing)
are possible. This affects fallocate(PUNCH_HOLE), mmap() and
write().
- SEAL: If SEAL_SEAL is set, no further seals can be added to a file.
This basically prevents the F_ADD_SEAL operation on a file and
can be set to prevent others from adding further seals that you
don't want.
The described use-cases can easily use these seals to provide safe use
without any trust-relationship:
1) The graphics server can verify that a passed file-descriptor has
SEAL_SHRINK set. This allows safe scanout, while the client is
allowed to increase buffer size for window-resizing on-the-fly.
Concurrent writes are explicitly allowed.
2) For general-purpose IPC, both processes can verify that SEAL_SHRINK,
SEAL_GROW and SEAL_WRITE are set. This guarantees that neither
process can modify the data while the other side parses it.
Furthermore, it guarantees that even with writable FDs passed to the
peer, it cannot increase the size to hit memory-limits of the source
process (in case the file-storage is accounted to the source).
The new API is an extension to fcntl(), adding two new commands:
F_GET_SEALS: Return a bitset describing the seals on the file. This
can be called on any FD if the underlying file supports
sealing.
F_ADD_SEALS: Change the seals of a given file. This requires WRITE
access to the file and F_SEAL_SEAL may not already be set.
Furthermore, the underlying file must support sealing and
there may not be any existing shared mapping of that file.
Otherwise, EBADF/EPERM is returned.
The given seals are _added_ to the existing set of seals
on the file. You cannot remove seals again.
The fcntl() handler is currently specific to shmem and disabled on all
files. A file needs to explicitly support sealing for this interface to
work. A separate syscall is added in a follow-up, which creates files that
support sealing. There is no intention to support this on other
file-systems. Semantics are unclear for non-volatile files and we lack any
use-case right now. Therefore, the implementation is specific to shmem.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch (of 6):
The i_mmap_writable field counts existing writable mappings of an
address_space. To allow drivers to prevent new writable mappings, make
this counter signed and prevent new writable mappings if it is negative.
This is modelled after i_writecount and DENYWRITE.
This will be required by the shmem-sealing infrastructure to prevent any
new writable mappings after the WRITE seal has been set. In case there
exists a writable mapping, this operation will fail with EBUSY.
Note that we rely on the fact that iff you already own a writable mapping,
you can increase the counter without using the helpers. This is the same
that we do for i_writecount.
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Ryan Lortie <desrt@desrt.ca>
Cc: Lennart Poettering <lennart@poettering.net>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes checkpatch warning:
WARNING: debugfs_remove(NULL) is safe this check is probably not required
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Christine Caulfield <ccaulfie@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now with 64bit bzImage and kexec tools, we support ramdisk that size is
bigger than 2g, as we could put it above 4G.
Found compressed initramfs image could not be decompressed properly. It
turns out that image length is int during decompress detection, and it
will become < 0 when length is more than 2G. Furthermore, during
decompressing len as int is used for inbuf count, that has problem too.
Change len to long, that should be ok as on 32 bit platform long is
32bits.
Tested with following compressed initramfs image as root with kexec.
gzip, bzip2, xz, lzma, lzop, lz4.
run time for populate_rootfs():
size name Nehalem-EX Westmere-EX Ivybridge-EX
9034400256 root_img : 26s 24s 30s
3561095057 root_img.lz4 : 28s 27s 27s
3459554629 root_img.lzo : 29s 29s 28s
3219399480 root_img.gz : 64s 62s 49s
2251594592 root_img.xz : 262s 260s 183s
2226366598 root_img.lzma: 386s 376s 277s
2901482513 root_img.bz2 : 635s 599s
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Rashika Kheria <rashika.kheria@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kyungsik Lee <kyungsik.lee@lge.com>
Cc: P J P <ppandit@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: "Daniel M. Weeks" <dan@danweeks.net>
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add DDEBUG in Makefile when CONFIG_QNX6FS_DEBUG is set. All QNX6DEBUG
messages are replaced by pr_debug which means debugging will be emitted in
debug level only and no more in error and info levels. debug uses now
pr_fmt and __func__
QNX6DEBUG definition has been removed.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joe Perches <joe@perches.com>
Cc: Kai Bankett <chaosman@ontika.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove "qnx6:" and "qnx6: " from each logging instruction.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joe Perches <joe@perches.com>
Cc: Kai Bankett <chaosman@ontika.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use current logging functions.
Coalesce formats.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joe Perches <joe@perches.com>
Cc: Kai Bankett <chaosman@ontika.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix checkpatch warning:
WARNING: Missing a blank line after declarations
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Remove "Error" in format logging (already in pr_ level)
- Use modulename in pr_fmt instead of ROMFS: in each pr_ callsites.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use current logging functions. Coalesce formats.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes some checkpatch errors/warnings:
WARNING: Missing a blank line after declarations
ERROR: spaces required around that '=' (ctx:VxV)
ERROR: "foo * bar" should be "foo *bar"
ERROR: space prohibited after that open parenthesis '('
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use module name for "cramfs: " prefix. (note that uncompress.c printk had
no prefix).
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use current logging functions. No level printk converted to pr_err
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All bfs related functions use bfs_ prefix. This patch also moves extern
declaration to bfs.h and removes prototype from inode.c
This fixes checkpatch warning:
WARNING: externs should be avoided in .c files
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: "Tigran A. Aivazian" <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Might as well do the right thing.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use kernel.h definition.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the final user, and the typedef itself.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We have a special check in read_vmcore() handler to check if the page was
reported as ram or not by the hypervisor (pfn_is_ram()). However, when
vmcore is read with mmap() no such check is performed. That can lead to
unpredictable results, e.g. when running Xen PVHVM guest memcpy() after
mmap() on /proc/vmcore will hang processing HVMMEM_mmio_dm pages creating
enormous load in both DomU and Dom0.
Fix the issue by mapping each non-ram page to the zero page. Keep direct
path with remap_oldmem_pfn_range() to avoid looping through all pages on
bare metal.
The issue can also be solved by overriding remap_oldmem_pfn_range() in
xen-specific code, as remap_oldmem_pfn_range() was been designed for.
That, however, would involve non-obvious xen code path for all x86 builds
with CONFIG_XEN_PVHVM=y and would prevent all other hypervisor-specific
code on x86 arch from doing the same override.
[fengguang.wu@intel.com: remap_oldmem_pfn_checked() can be static]
[akpm@linux-foundation.org: clean up layout]
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm initialization on fork/exec is spread all over the place, which makes
the code look inconsistent.
We have mm_init(), which is supposed to init/nullify mm's internals, but
it doesn't init all the fields it should:
- on fork ->mmap,mm_rb,vmacache_seqnum,map_count,mm_cpumask,locked_vm
are zeroed in dup_mmap();
- on fork ->pmd_huge_pte is zeroed in dup_mm(), immediately before
calling mm_init();
- ->cpu_vm_mask_var ptr is initialized by mm_init_cpumask(), which is
called before mm_init() on both fork and exec;
- ->context is initialized by init_new_context(), which is called after
mm_init() on both fork and exec;
Let's consolidate all the initializations in mm_init() to make the code
look cleaner.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If you're applying this patch, all /proc/$PID/* files were converted
to seq_file interface and this code became unused.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
/proc/tty/ldisc appear to be unused as a directory and
it had been always that way.
But it is userspace visible thing.
Cowardly remove only in-kernel variable holding it.
[akpm@linux-foundation.org: add comment]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently lookup for /proc/$PID first goes through spinlock and whole list
of misc /proc entries only to confirm that, yes, /proc/42 can not possibly
match random proc entry.
List is is several dozens entries long (52 entries on my setup).
None of this is necessary.
Try to convert dentry name to integer first.
If it works, it must be /proc/$PID.
If it doesn't, it must be random proc entry.
Based on patch from Al Viro.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* remove proc_create(NULL, ...) check, let it oops
* warn about proc_create("", ...) and proc_create("very very long name", ...)
proc code keeps length as u8, no 256+ name length possible
* warn about proc_create("123", ...)
/proc/$PID and /proc/misc namespaces are separate things,
but dumb module might create funky a-la $PID entry.
* remove post mortem strchr('/') check
Triggering it implies either strchr() is buggy or memory corruption.
It should be VFS check anyway.
In reality, none of these checks will ever trigger,
it is preparation for the next patch.
Based on patch from Al Viro.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
proc_uid_seq_operations, proc_gid_seq_operations and
proc_projid_seq_operations are only called in proc_id_map_open with
seq_open as const struct seq_operations so we can constify the 3
structures and update proc_id_map_open prototype.
text data bss dec hex filename
6817 404 1984 9205 23f5 kernel/user_namespace.o-before
6913 308 1984 9205 23f5 kernel/user_namespace.o-after
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix checkpatch warning:
WARNING: Missing a blank line after declarations
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert no level printk to pr_debug in UFSD. DEBUG is defined with
CONFIG_UFS_DEBUG so pr_debug are emitted here.
Also fixing call to UFSD (add;)
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace approximate function name by __func__ using standard format
"function():"
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace UFS-fs, UFS-fs: and UFS: by pr_fmt with module name "ufs: "
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use current logging functions.
- no level printk under CONFIG_UFS_DEBUG converted to pr_debug
- no level printk elsewhere converted to pr_err
- add DDEBUG flag in Makefile
- coalesce formats
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch integrates creation of sysfs groups and
attributes into NILFS file system driver.
It was found the issue with nilfs_sysfs_{create/delete}_snapshot_group
functions by Michael L Semon <mlsemon35@gmail.com> in the first
version of the patch:
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:579
in_atomic(): 1, irqs_disabled(): 0, pid: 32676, name: umount.nilfs2
2 locks held by umount.nilfs2/32676:
#0: (&type->s_umount_key#21){++++..}, at: [<790c18e2>] deactivate_super+0x37/0x58
#1: (&(&nilfs->ns_cptree_lock)->rlock){+.+...}, at: [<791bf659>] nilfs_put_root+0x23/0x5a
Preemption disabled at:[<791bf659>] nilfs_put_root+0x23/0x5a
CPU: 0 PID: 32676 Comm: umount.nilfs2 Not tainted 3.14.0+ #2
Hardware name: Dell Computer Corporation Dimension 2350/07W080, BIOS A01 12/17/2002
Call Trace:
dump_stack+0x4b/0x75
__might_sleep+0x111/0x16f
mutex_lock_nested+0x1e/0x3ad
kernfs_remove+0x12/0x26
sysfs_remove_dir+0x3d/0x62
kobject_del+0x13/0x38
nilfs_sysfs_delete_snapshot_group+0xb/0xd
nilfs_put_root+0x2a/0x5a
nilfs_detach_log_writer+0x1ab/0x2c1
nilfs_put_super+0x13/0x68
generic_shutdown_super+0x60/0xd1
kill_block_super+0x1d/0x60
deactivate_locked_super+0x22/0x3f
deactivate_super+0x3e/0x58
mntput_no_expire+0xe2/0x141
SyS_oldumount+0x70/0xa5
syscall_call+0x7/0xb
The reason of the issue was placement of
nilfs_sysfs_{create/delete}_snapshot_group() call under
nilfs->ns_cptree_lock protection. But this protection is unnecessary and
wrong solution. The second version of the patch fixes this issue.
[fengguang.wu@intel.com: nilfs_sysfs_create_mounted_snapshots_group can be static]
Reported-by: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds creation of <snapshot> group for every mounted
snapshot in /sys/fs/nilfs2/<device>/mounted_snapshots group.
The group contains details about mounted snapshot:
(1) inodes_count - show number of inodes for snapshot.
(2) blocks_count - show number of blocks for snapshot.
Signed-off-by: Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds creation of /sys/fs/nilfs2/<device>/mounted_snapshots
group.
The mounted_snapshots group contains group for every
mounted snapshot.
Signed-off-by: Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds creation of /sys/fs/nilfs2/<device>/checkpoints
group.
The checkpoints group contains attributes that describe
details about volume's checkpoints:
(1) checkpoints_number - show number of checkpoints on volume.
(2) snapshots_number - show number of snapshots on volume.
(3) last_seg_checkpoint - show checkpoint number of the latest segment.
(4) next_checkpoint - show next checkpoint number.
Signed-off-by: Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds creation of /sys/fs/nilfs2/<device>/segments
group.
The segments group contains attributes that describe
details about volume's segments:
(1) segments_number - show number of segments on volume.
(2) blocks_per_segment - show number of blocks in segment.
(3) clean_segments - show count of clean segments.
(4) dirty_segments - show count of dirty segments.
Signed-off-by: Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds creation of /sys/fs/nilfs2/<device>/segctor
group.
The segctor group contains attributes that describe
segctor thread activity details:
(1) last_pseg_block - show start block number of the latest segment.
(2) last_seg_sequence - show sequence value of the latest segment.
(3) last_seg_checkpoint - show checkpoint number of the latest segment.
(4) current_seg_sequence - show segment sequence counter.
(5) current_last_full_seg - show index number of the latest full segment.
(6) next_full_seg - show index number of the full segment index
to be used next.
(7) next_pseg_offset - show offset of next partial segment in
the current full segment.
(8) next_checkpoint - show next checkpoint number.
(9) last_seg_write_time - show write time of the last segment
in human-readable format.
(10) last_seg_write_time_secs - show write time of the last segment
in seconds.
(11) last_nongc_write_time - show write time of the last segment
not for cleaner operation in human-readable format.
(12) last_nongc_write_time_secs - show write time of the last segment
not for cleaner operation in seconds.
(13) dirty_data_blocks_count - show number of dirty data blocks.
Signed-off-by: Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds creation of /sys/fs/nilfs2/<device>/superblock
group.
The superblock group contains attributes that describe
superblock's details:
(1) sb_write_time - show previous write time of super block in
human-readable format.
(2) sb_write_time_secs - show previous write time of super block
in seconds.
(3) sb_write_count - show write count of super block.
(4) sb_update_frequency - show/set interval of periodical update
of superblock (in seconds). You can set preferable frequency of
superblock update by command:
echo <value> > /sys/fs/nilfs2/<device>/superblock/sb_update_frequency
Signed-off-by: Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds creation of /sys/fs/nilfs2/<device> group.
The <device> group contains attributes that describe file
system partition's details:
(1) revision - show NILFS file system revision.
(2) blocksize - show volume block size in bytes.
(3) device_size - show volume size in bytes.
(4) free_blocks - show count of free blocks on volume.
(5) uuid - show volume's UUID.
(6) volume_name - show volume's name.
Signed-off-by: Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patchset implements creation of sysfs groups and attributes with
the purpose to show NILFS2 volume details, internal state of the driver
and to manage internal state of NILFS2 driver.
Sysfs is a virtual file system that exports information about devices
and drivers from the kernel device model to user space, and is also used
for configuration. NILFS2 is a complex file system that has segctor
thread, GC thread, checkpoint/snapshot model and so on. Sysfs namespace
provides native and easy way for: (1) getting info and statistics about
volume state; (2) getting info and configuration of internal subsystems
(segctor thread); (3) snapshots management.
Suggested patchset provides basis for managing segctor thread behaviour
and manipulation by snapshots. Currently, it informs only about segctor
thread's internal parameters and about mounted snapshots. But sysfs
interface can provide easy and simple way for deep management of segctor
thread and snapshots.
This patchset provides opportunity to manage interval of periodical
update of superblock (in seconds). Default value is 10 seconds. Now a
user can increase this value by means of
nilfs2/<device>/superblock/sb_update_frequency attribute in the case of
necessity.
Also the patchset provides opportunity to get information easily about
key volumes's parameters (free blocks, superblock write count,
superblock update frequency, latest segment info, dirty data blocks
count, count of clean segments, count of dirty segments and so on) in
real time manner. Such information can be used in scripts for subtle
management of filesystem.
Implemented functionality creates such groups:
(1) /sys/fs/nilfs2 - root group
(2) /sys/fs/nilfs2/features - group contains attributes that describe NILFS
file system driver features
(3) /sys/fs/nilfs2/<device> - group contains attributes that describe file
system partition's details
(4) /sys/fs/nilfs2/<device>/superblock - group contains attributes that describe
superblock's details
(5) /sys/fs/nilfs2/<device>/segctor - group contains attributes that describe
segctor thread activity details
(6) /sys/fs/nilfs2/<device>/segments - group contains attributes that describe
details about volume's segments
(7) /sys/fs/nilfs2/<device>/checkpoints - group contains attributes that describe
details about volume's checkpoints
(8) /sys/fs/nilfs2/<device>/mounted_snapshots - group contains group for every
mounted snapshot
(9) /sys/fs/nilfs2/<device>/mounted_snapshots/<snapshot> - group contains
details about mounted snapshot
This patch (of 9):
This patch adds code of creation /sys/fs/nilfs2 group and
/sys/fs/nilfs2/features group.
The features group contains attributes that describe NILFS
file system driver features:
(1) revision - show current revision of NILFS file system driver.
There are two formats of timestamp output - seconds and human-readable
format. Every showed timestamp has two sysfs files (time-<xxx> and
time-<xxx>-secs). One sysfs file (time-<xxx>) shows time in
human-readable format. Another sysfs file (time-<xxx>-secs) shows time in
seconds.
It was reported by Michael Semon that timestamp output in human-readable
format should be changed from "2014-4-12 14:5:38" to "2014-04-12
14:05:38". Second version of the patch fixes this issue.
Reported-by: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Vyacheslav Dubeyko <Vyacheslav.Dubeyko@hgst.com>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
befs_dump_super_block was called between befs_load_sb and befs_check_sb.
It has been reported to crash (5/900) with null block testing.
This patch loads, checks and only dump superblock if it's a valid one
then brelse bh.
(befs_dump_super_block uses disk_sb (bh->b_data) so it seems we need to
call it before brelse(bh) but I don't know why befs_check_sb was called
after brelse. Another thing I don't understand is why this problem
appears now).
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The original minix zmap blocks calculation was correct, in the formula of:
sbi->s_nzones - sbi->s_firstdatazone + 1
It is
sp->s_zones - (sp->s_firstdatazone - 1)
in the minix3 source code.
But a later commit 016e8d44bc ("fs/minix: Verify bitmap block counts
before mounting") has changed it unfortunately as:
sbi->s_nzones - (sbi->s_firstdatazone + 1)
This would show free blocks one block less than the real when the total
data blocks are in "full zmap blocks plus one".
This patch corrects that zmap blocks calculation and tidy a printk
message while at it.
Signed-off-by: Qi Yong <qiyong@fc-cn.com>
Cc: Josh Boyer <jwboyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the expiring_list is empty, we can avoid a costly spinlock in the
rcu-walk path through autofs4_d_manage (once the rest of the path
becomes rcu-walk friendly).
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The variable 'ino' already exists and already has the correct value.
The d_fsdata of a dentry is never changed after the d_fsdata is
instantiated, so this new assignment cannot be necessary.
It was introduced in commit b5b801779d ("autofs4: Add d_manage()
dentry operation").
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix checkpatch errors:
"ERROR: return is not a function, parentheses are not required"
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I believe this can only happen in the case of a corrupted filesystem.
So -EIO looks like the appropriate error.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If we get to this point and discover the dentry is not a root dentry, or
not DCACHE_DISCONNECTED--great, we always prefer that anyway.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
There are a few d_obtain_alias callers that are using it to get the
root of a filesystem which may already have an alias somewhere else.
This is not the same as the filehandle-lookup case, and none of them
actually need DCACHE_DISCONNECTED set.
It isn't really a serious problem, but it would really be clearer if we
reserved DCACHE_DISCONNECTED for those cases where it's actually needed.
In the btrfs case this was causing a spurious printk from
nfsd/nfsfh.c:fh_verify when it found an unexpected DCACHE_DISCONNECTED
dentry. Josef worked around this by unsetting DCACHE_DISCONNECTED
manually in 3a0dfa6a12 "Btrfs: unset DCACHE_DISCONNECTED when mounting
default subvol", and this replaces that workaround.
Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Any IS_ROOT() alias should be safe to use; there's nothing special about
DCACHE_DISCONNECTED dentries.
Note that this is in fact useful for filesystems such as btrfs which can
legimately encounter a directory with a preexisting IS_ROOT alias on a
lookup that crosses into a subvolume. (Those aliases are currently
marked DCACHE_DISCONNECTED--but not really for any good reason, and
we'll change that soon.)
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Currently if d_splice_alias finds a directory with an alias that is not
IS_ROOT or not DCACHE_DISCONNECTED, it creates a duplicate directory.
Duplicate directory dentries are unacceptable; it is better just to
error out.
(In the case of a local filesystem the most likely case is filesystem
corruption: for example, perhaps two directories point to the same child
directory, and the other parent has already been found and cached.)
Note that distributed filesystems may encounter this case in normal
operation if a remote host moves a directory to a location different
from the one we last cached in the dcache. For that reason, such
filesystems should instead use d_materialise_unique, which tries to move
the old directory alias to the right place instead of erroring out.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
d_splice_alias will d_move an IS_ROOT() directory dentry into place if
one exists. This should be safe as long as the dentry remains IS_ROOT,
but I can't see what guarantees that: once we drop the i_lock all we
hold here is the i_mutex on an unrelated parent directory.
Instead copy the logic of d_materialise_unique.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Just a trivial move to locate it near (similar) d_materialise_unique
code and save some forward references in a following patch.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Looks like the directory loop check is actually done in renameat?
Whatever, leave this out rather than trying to keep it up to date with
the code.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In REF-walk mode, ->d_manage can return -EISDIR to indicate
that the dentry is not really a mount trap (or even a mount point)
and that any mounts or any DCACHE_NEED_AUTOMOUNT flag should be
ignored.
RCU-walk mode doesn't currently support this, so if there is a dentry
with DCACHE_NEED_AUTOMOUNT set but which shouldn't be a mount-trap,
lookup_fast() will always drop in REF-walk mode.
With this patch, an -EISDIR from ->d_manage will always cause mounts
and automounts to be ignored, both in REF-walk and RCU-walk.
Bug-fixed-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Ian Kent <raven@themaw.net>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This flag gives CIFS the ability to support its native rename semantics.
Implementation is simple: just bail out before trying to hack around the
noreplace semantics.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Steve French <smfrench@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Support RENAME_NOREPLACE and RENAME_EXCHANGE flags on hostfs if the
underlying filesystem supports it.
Since renameat2(2) is not yet in any libc, use syscall(2) to invoke the
renameat2 syscall.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
RENAME_NOREPLACE is trivial to implement for most filesystems: switch over
to ->rename2() and check for the supported flags. The rest is done by the
VFS.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Chris Mason <clm@fb.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
so we return -EIO instead of -EINVAL.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Christoph Hellwig suggests:
1) make vfs_rename call ->rename2 if it exists instead of ->rename
2) switch all filesystems that you're adding NOREPLACE support for to
use ->rename2
3) see how many ->rename instances we'll have left after a few
iterations of 2.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Rather than playing silly buggers with vfsmount refcounts, just have
acct_on() ask fs/namespace.c for internal clone of file->f_path.mnt
and replace it with said clone. Then attach the pin to original
vfsmount. Voila - the clone will be alive until the file gets closed,
making sure that underlying superblock remains active, etc., and
we can drop the original vfsmount, so that it's not kept busy.
If the file lives until the final mntput of the original vfsmount,
we'll notice that there's an fs_pin (one in bsd_acct_struct that
holds that file) and mnt_pin_kill() will take it out. Since
->kill() is synchronous, we won't proceed past that point until
these files are closed (and private clones of our vfsmount are
gone), so we get the same ordering warranties we used to get.
mnt_pin()/mnt_unpin()/->mnt_pinned is gone now, and good riddance -
it never became usable outside of kernel/acct.c (and racy wrt
umount even there).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
These externs belong in fs/internal.h. Rename (they are not acct-specific
anymore) and move them over there.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add a new field to fs_pin - kill(pin). That's what umount and r/o remount
will be calling for all pins attached to vfsmount and superblock resp.
Called after bumping the refcount, so it won't go away under us. Dropping
the refcount is responsibility of the instance. All generic stuff moved to
fs/fs_pin.c; the next step will rip all the knowledge of kernel/acct.c from
fs/super.c and fs/namespace.c. After that - death to mnt_pin(); it was
intended to be usable as generic mechanism for code that wants to attach
objects to vfsmount, so that they would not make the sucker busy and
would get killed on umount. Never got it right; it remained acct.c-specific
all along. Now it's very close to being killable.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
just repeat the frozen check after regaining it, and check that sb
is still alive. If several threads hit acct_auto_close() at the
same time, acct_auto_close() will survive that just fine. And we
really don't want to play with writes and closing the file with
->s_umount held exclusive - it's a deadlock country.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Put these suckers on per-vfsmount and per-superblock lists instead.
Note: right now it's still acct_lock for everything, but that's
going to change.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
