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11222 commits

Author SHA1 Message Date
Steven Whitehouse b52896813c GFS2: Fix bug in gfs2_lock_fs_check_clean()
gfs2_lock_fs_check_clean() should not be calling gfs2_jindex_hold()
since it doesn't work like rindex hold, despite the comment. That
allows gfs2_jindex_hold() to be moved into ops_fstype.c where it
can be made static.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:11 +00:00
Steven Whitehouse fdd1062eba GFS2: Send some sensible sysfs stuff
We ought to inform the user of the locktable and lockproto for each
uevent we generate.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:10 +00:00
Steven Whitehouse 97cc1025b1 GFS2: Kill two daemons with one patch
This patch removes the two daemons, gfs2_scand and gfs2_glockd
and replaces them with a shrinker which is called from the VM.

The net result is that GFS2 responds better when there is memory
pressure, since it shrinks the glock cache at the same rate
as the VFS shrinks the dcache and icache. There are no longer
any time based criteria for shrinking glocks, they are kept
until such time as the VM asks for more memory and then we
demote just as many glocks as required.

There are potential future changes to this code, including the
possibility of sorting the glocks which are to be written back
into inode number order, to get a better I/O ordering. It would
be very useful to have an elevator based workqueue implementation
for this, as that would automatically deal with the read I/O cases
at the same time.

This patch is my answer to Andrew Morton's remark, made during
the initial review of GFS2, asking why GFS2 needs so many kernel
threads, the answer being that it doesn't :-) This patch is a
net loss of about 200 lines of code.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:09 +00:00
Steven Whitehouse 9ac1b4d9b6 GFS2: Move gfs2_recoverd into recovery.c
By moving gfs2_recoverd, we can make an additional function static
and it also leaves only (the already scheduled for removal) gfs2_glockd
in daemon.c.

At the same time the declaration of gfs2_quotad is moved to quota.h
to reflect the new location of gfs2_quotad in a previous patch. Also
the recovery.h and quota.h headers are cleaned up.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:07 +00:00
Steven Whitehouse 813e0c46c9 GFS2: Fix "truncate in progress" hang
Following on from the recent clean up of gfs2_quotad, this patch moves
the processing of "truncate in progress" inodes from the glock workqueue
into gfs2_quotad. This fixes a hang due to the "truncate in progress"
processing requiring glocks in order to complete.

It might seem odd to use gfs2_quotad for this particular item, but
we have to use a pre-existing thread since creating a thread implies
a GFP_KERNEL memory allocation which is not allowed from the glock
workqueue context. Of the existing threads, gfs2_logd and gfs2_recoverd
may deadlock if used for this operation. gfs2_scand and gfs2_glockd are
both scheduled for removal at some (hopefully not too distant) future
point. That leaves only gfs2_quotad whose workload is generally fairly
light and is easily adapted for this extra task.

Also, as a result of this change, it opens the way for a future patch to
make the reading of the inode's information asynchronous with respect to
the glock workqueue, which is another improvement that has been on the list
for some time now.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:06 +00:00
Steven Whitehouse 37b2c8377c GFS2: Clean up & move gfs2_quotad
This patch is a clean up of gfs2_quotad prior to giving it an
extra job to do in addition to the current portfolio of updating
the quota and statfs information from time to time.

As a result it has been moved into quota.c allowing one of the
functions it calls to be made static. Also the clean up allows
the two existing functions to have separate timeouts and also
to coexist with its future role of dealing with the "truncate in
progress" inode flag.

The (pointless) setting of gfs2_quotad_secs is removed since we
arrange to only wake up quotad when one of the two timers expires.

In addition the struct gfs2_quota_data is moved into a slab cache,
mainly for easier debugging. It should also be possible to use
a shrinker in the future, rather than the current scheme of scanning
the quota data entries from time to time.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:05 +00:00
Steven Whitehouse fa75cedc3d GFS2: Add more detail to debugfs glock dumps
Although the glock dumps print quite a lot of information about
the glocks themselves, there are more things which can be
usefully added to the dump realting to the objects themselves.

This patch adds a few more fields to the inode and resource
group lines, which should be useful for debugging.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:04 +00:00
Steven Whitehouse 73f749483e GFS2: Banish struct gfs2_rgrpd_host
This patch moves the final field so that we can get rid
of struct gfs2_rgrpd_host, as promised some time ago. Also
by rearranging the fields slightly, we are able to reduce
the size of the gfs2_rgrpd structure at the same time.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:03 +00:00
Steven Whitehouse cfc8b54922 GFS2: Move rg_free from gfs2_rgrpd_host to gfs2_rgrpd
The second of three fields which need to move, in order
to remove the struct gfs2_rgrpd_host.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:02 +00:00
Steven Whitehouse d8b71f7381 GFS2: Move rg_igeneration into struct gfs2_rgrpd
This moves one of the fields of struct gfs2_rgrpd_host into
the struct gfs2_rgrpd with the eventual aim of removing
the struct rgrpd_host completely.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:01 +00:00
Steven Whitehouse 383f01fbf4 GFS2: Banish struct gfs2_dinode_host
The final field in gfs2_dinode_host was the i_flags field. Thats
renamed to i_diskflags in order to avoid confusion with the existing
inode flags, and moved into the inode proper at a suitable location
to avoid creating a "hole".

At that point struct gfs2_dinode_host is no longer needed and as
promised (quite some time ago!) it can now be removed completely.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:38:59 +00:00
Steven Whitehouse c9e9888677 GFS2: Move i_size from gfs2_dinode_host and rename it to i_disksize
This patch moved the i_size field from the gfs2_dinode_host and
following the ext3 convention renames it i_disksize.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:38:58 +00:00
Steven Whitehouse 3767ac21f4 GFS2: Move di_eattr into "proper" inode
This moves the di_eattr field out of gfs2_inode_host and
into the inode proper.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:38:57 +00:00
Steven Whitehouse ad6203f2b4 GFS2: Move "entries" into "proper" inode
This moves the directory entry count into the proper inode.
Potentially we could get this to share the space used by
something else in the future, but this is one more step
on the way to removing the gfs2_dinode_host structure.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:38:56 +00:00
Steven Whitehouse bcf0b5b348 GFS2: Move generation number into "proper" part of inode
This moves the generation number from the gfs2_dinode_host
into the gfs2_inode structure. Eventually the plan is to get
rid of the gfs2_dinode_host structure completely.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:38:55 +00:00
Harvey Harrison 55ba474dae GFS2: sparse annotation of gl->gl_spin
fs/gfs2/glock.c:308:5: warning: context problem in 'do_promote': '_spin_unlock' expected different context
fs/gfs2/glock.c:308:5:    context '*gl+28': wanted >= 1, got 0
fs/gfs2/glock.c:529:2: warning: context problem in 'do_xmote': '_spin_unlock' expected different context
fs/gfs2/glock.c:529:2:    context '*gl+28': wanted >= 1, got 0
fs/gfs2/glock.c:925:3: warning: context problem in 'add_to_queue': '_spin_unlock' expected different context
fs/gfs2/glock.c:925:3:    context '*gl+28': wanted >= 1, got 0

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:38:50 +00:00
Steven Whitehouse 1bb7322fd0 GFS2: Fix up jdata writepage/delete_inode
There is a bug in writepage and delete_inode which allows jdata files to
invalidate pages from the address space without being in a transaction at
the time. This causes problems in case the pages are in the journal. This
patch fixes that case and prevents the resulting oops.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:38:49 +00:00
Steven Whitehouse b276058371 GFS2: Rationalise header files
Move the contents of some headers which contained very
little into more sensible places, and remove the original
header files. This should make it easier to find things.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:38:48 +00:00
Steven Whitehouse e9079cce20 GFS2: Support for FIEMAP ioctl
This patch implements the FIEMAP ioctl for GFS2. We can use the generic
code (aside from a lock order issue, solved as per Ted Tso's suggestion)
for which I've introduced a new variant of the generic function. We also
have one exception to deal with, namely stuffed files, so we do that
"by hand", setting all the required flags.

This has been tested with a modified (I could only find an old version) of
Eric's test program, and appears to work correctly.

This patch does not currently support FIEMAP of xattrs, but the plan is to add
that feature at some future point.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Theodore Tso <tytso@mit.edu>
Cc: Eric Sandeen <sandeen@redhat.com>
2009-01-05 07:38:46 +00:00
Linus Torvalds fe0bdec68b Merge branch 'audit.b61' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current
* 'audit.b61' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
  audit: validate comparison operations, store them in sane form
  clean up audit_rule_{add,del} a bit
  make sure that filterkey of task,always rules is reported
  audit rules ordering, part 2
  fixing audit rule ordering mess, part 1
  audit_update_lsm_rules() misses the audit_inode_hash[] ones
  sanitize audit_log_capset()
  sanitize audit_fd_pair()
  sanitize audit_mq_open()
  sanitize AUDIT_MQ_SENDRECV
  sanitize audit_mq_notify()
  sanitize audit_mq_getsetattr()
  sanitize audit_ipc_set_perm()
  sanitize audit_ipc_obj()
  sanitize audit_socketcall
  don't reallocate buffer in every audit_sockaddr()
2009-01-04 16:32:11 -08:00
Nick Piggin 54566b2c15 fs: symlink write_begin allocation context fix
With the write_begin/write_end aops, page_symlink was broken because it
could no longer pass a GFP_NOFS type mask into the point where the
allocations happened.  They are done in write_begin, which would always
assume that the filesystem can be entered from reclaim.  This bug could
cause filesystem deadlocks.

The funny thing with having a gfp_t mask there is that it doesn't really
allow the caller to arbitrarily tinker with the context in which it can be
called.  It couldn't ever be GFP_ATOMIC, for example, because it needs to
take the page lock.  The only thing any callers care about is __GFP_FS
anyway, so turn that into a single flag.

Add a new flag for write_begin, AOP_FLAG_NOFS.  Filesystems can now act on
this flag in their write_begin function.  Change __grab_cache_page to
accept a nofs argument as well, to honour that flag (while we're there,
change the name to grab_cache_page_write_begin which is more instructive
and does away with random leading underscores).

This is really a more flexible way to go in the end anyway -- if a
filesystem happens to want any extra allocations aside from the pagecache
ones in ints write_begin function, it may now use GFP_KERNEL (rather than
GFP_NOFS) for common case allocations (eg.  ocfs2_alloc_write_ctxt, for a
random example).

[kosaki.motohiro@jp.fujitsu.com: fix ubifs]
[kosaki.motohiro@jp.fujitsu.com: fix fuse]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Cleaned up the calling convention: just pass in the AOP flags
  untouched to the grab_cache_page_write_begin() function.  That
  just simplifies everybody, and may even allow future expansion of the
  logic.   - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-04 13:33:20 -08:00
Pekka Enberg c644f0e4b5 fs: introduce bgl_lock_ptr()
As suggested by Andreas Dilger, introduce a bgl_lock_ptr() helper in
<linux/blockgroup_lock.h> and add separate sb_bgl_lock() helpers to
filesystem specific header files to break the hidden dependency to
struct ext[234]_sb_info.

Also, while at it, convert the macros to static inlines to try make up
for all the times I broke Andrew Morton's tree.

Acked-by: Andreas Dilger <adilger@sun.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-04 13:33:20 -08:00
Al Viro 157cf649a7 sanitize audit_fd_pair()
* no allocations
* return void

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04 15:14:41 -05:00
Linus Torvalds 7d3b56ba37 Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (77 commits)
  x86: setup_per_cpu_areas() cleanup
  cpumask: fix compile error when CONFIG_NR_CPUS is not defined
  cpumask: use alloc_cpumask_var_node where appropriate
  cpumask: convert shared_cpu_map in acpi_processor* structs to cpumask_var_t
  x86: use cpumask_var_t in acpi/boot.c
  x86: cleanup some remaining usages of NR_CPUS where s/b nr_cpu_ids
  sched: put back some stack hog changes that were undone in kernel/sched.c
  x86: enable cpus display of kernel_max and offlined cpus
  ia64: cpumask fix for is_affinity_mask_valid()
  cpumask: convert RCU implementations, fix
  xtensa: define __fls
  mn10300: define __fls
  m32r: define __fls
  h8300: define __fls
  frv: define __fls
  cris: define __fls
  cpumask: CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
  cpumask: zero extra bits in alloc_cpumask_var_node
  cpumask: replace for_each_cpu_mask_nr with for_each_cpu in kernel/time/
  cpumask: convert mm/
  ...
2009-01-03 12:04:39 -08:00
Al Viro 3bfacef412 get rid of special-casing the /sbin/loader on alpha
... just make it a binfmt handler like #! one.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-03 11:45:54 -08:00
Al Viro 17580d7f2f sanitize ifdefs in binfmt_aout
They are actually alpha vs.  i386/arm/m68k i.e. ecoff vs. aout.

In the only place where we actually tried to handle arm and i386/m68k in
different ways (START_DATA() in coredump handling), the arm variant
works for all of them (i386 and m68k have u.start_code set to 0).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-03 11:45:54 -08:00
Al Viro fe30af971d remove the rudiment of a.out for sparc
it's been used only in sunos compat

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-03 11:45:54 -08:00
Linus Torvalds 8e3bda0863 Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6
* 'linux-next' of git://git.infradead.org/ubifs-2.6: (33 commits)
  UBIFS: add more useful debugging prints
  UBIFS: print debugging messages properly
  UBIFS: fix numerous spelling mistakes
  UBIFS: allow mounting when short of space
  UBIFS: fix writing uncompressed files
  UBIFS: fix checkpatch.pl warnings
  UBIFS: fix sparse warnings
  UBIFS: simplify make_free_space
  UBIFS: do not lie about used blocks
  UBIFS: restore budg_uncommitted_idx
  UBIFS: always commit on unmount
  UBIFS: use ubi_sync
  UBIFS: always commit in sync_fs
  UBIFS: fix file-system synchronization
  UBIFS: fix constants initialization
  UBIFS: avoid unnecessary calculations
  UBIFS: re-calculate min_idx_size after the commit
  UBIFS: use nicer 64-bit math
  UBIFS: fix available blocks count
  UBIFS: various comment improvements and fixes
  ...
2009-01-02 15:57:47 -08:00
Linus Torvalds 597b0d2162 Merge branch 'kvm-updates/2.6.29' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm
* 'kvm-updates/2.6.29' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm: (140 commits)
  KVM: MMU: handle large host sptes on invlpg/resync
  KVM: Add locking to virtual i8259 interrupt controller
  KVM: MMU: Don't treat a global pte as such if cr4.pge is cleared
  MAINTAINERS: Maintainership changes for kvm/ia64
  KVM: ia64: Fix kvm_arch_vcpu_ioctl_[gs]et_regs()
  KVM: x86: Rework user space NMI injection as KVM_CAP_USER_NMI
  KVM: VMX: Fix pending NMI-vs.-IRQ race for user space irqchip
  KVM: fix handling of ACK from shared guest IRQ
  KVM: MMU: check for present pdptr shadow page in walk_shadow
  KVM: Consolidate userspace memory capability reporting into common code
  KVM: Advertise the bug in memory region destruction as fixed
  KVM: use cpumask_var_t for cpus_hardware_enabled
  KVM: use modern cpumask primitives, no cpumask_t on stack
  KVM: Extract core of kvm_flush_remote_tlbs/kvm_reload_remote_mmus
  KVM: set owner of cpu and vm file operations
  anon_inodes: use fops->owner for module refcount
  x86: KVM guest: kvm_get_tsc_khz: return khz, not lpj
  KVM: MMU: prepopulate the shadow on invlpg
  KVM: MMU: skip global pgtables on sync due to cr3 switch
  KVM: MMU: collapse remote TLB flushes on root sync
  ...
2009-01-02 11:41:11 -08:00
David Howells d0eafc7db8 CRED: Wrap task credential accesses in the devpts filesystem
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>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:38 -08:00
Andrew Morton 8c056e5b14 devpts: fix unused function warning
fs/devpts/inode.c:324: warning: 'compare_init_pts_sb' defined but not used

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:37 -08:00
Alan Cox 835aa440f1 devpts: Coding style clean up
Just nail the oddments now while this code is being touched

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:36 -08:00
Sukadev Bhattiprolu 2a1b2dc0c8 Enable multiple instances of devpts
To support containers, allow multiple instances of devpts filesystem, such
that indices of ptys allocated in one instance are independent of ptys
allocated in other instances of devpts.

But to preserve backward compatibility, enable this support for multiple
instances only if:

	- CONFIG_DEVPTS_MULTIPLE_INSTANCES is set to Y, and
	- '-o newinstance' mount option is specified while mounting devpts

To use multi-instance mount, a container startup script could:

	$ ns_exec -cm /bin/bash
	$ umount /dev/pts
	$ mount -t devpts -o newinstance lxcpts /dev/pts
	$ mount -o bind /dev/pts/ptmx /dev/ptmx
	$ /usr/sbin/sshd -p 1234

where 'ns_exec -cm /bin/bash' is calls clone() with CLONE_NEWNS flag and execs
/bin/bash in the child process. A pty created by the sshd is not visible in
the original mount of /dev/pts.

USER-SPACE-IMPACT:
	- See Documentation/fs/devpts.txt (included in next patch) for user-
	  space impact in multi-instance and mixed-mode operation.
TODO:
	- Update mount(8), pts(4) man pages. Highlight impact of not
	  redirecting /dev/ptmx to /dev/pts/ptmx after a multi-instance mount.

Changelog[v6]:
	- [Dave Hansen] Use new get_init_pts_sb() interface
	- [Serge Hallyn] Don't bother displaying 'newinstance' in show_options
	- [Serge Hallyn] Use macros (PARSE_REMOUNT/PARSE_MOUNT) instead of 0/1.
	- [Serge Hallyn] Check error return from get_sb_single() (now
	  get_init_pts_sb())
	- devpts_pty_kill(): don't dput error dentries

Changelog[v5]:
	- Move get_sb_ref() definition to earlier patch
	- Move usage info to Documentation/filesystems/devpts.txt (next patch)
	- Make ptmx node even in init_pts_ns, now that default mode is 0000
	  (defined in earlier patch, enabled here).
	- Cache ptmx dentry and use to update mode during remount
	  (defined in earlier patch, enabled here).
	- Bugfix: explicitly ignore newinstance on remount (if newinstance was
	  specified on remount of initial mount, it would be ignored but
	  /proc/mounts would imply that the option was set)

Changelog[v4]:

	- Update patch description to address H. Peter Anvin's comments
	- Consolidate multi-instance mode code under new config token,
	  CONFIG_DEVPTS_MULTIPLE_INSTANCE.
	- Move usage-details from patch description to
	  Documentation/fs/devpts.txt

Changelog[v3]:
	- Rename new mount option to 'newinstance'
	- Create ptmx nodes only in 'newinstance' mounts
	- Bugfix: parse_mount_options() modifies @data but since we need to
	  parse the @data twice (once in devpts_get_sb() and once during
	  do_remount_sb()), parse a local copy of @data in devpts_get_sb().
	  (restructured code in devpts_get_sb() to fix this)

Changelog[v2]:
	- Support both single-mount and multiple-mount semantics and
	  provide '-onewmnt' option to select the semantics.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:36 -08:00
Sukadev Bhattiprolu d4076ac55b Define get_init_pts_sb()
See comments in the function header for details. The new interface will
be used in a follow-on patch.

Changelog [v2]:
	[Dave Hansen] Replace get_sb_ref() in fs/super.c with get_init_pts_sb()
	and make the new interface private to devpts

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:36 -08:00
Sukadev Bhattiprolu 1f8f1e2965 Define mknod_ptmx()
/dev/ptmx is closely tied to the devpts filesystem. An open of /dev/ptmx,
allocates the next pty index and the associated device shows up in the
devpts fs as /dev/pts/n.

Wih multiple instancs of devpts filesystem, during an open of /dev/ptmx
we would be unable to determine which instance of the devpts is being
accessed.

So we move the 'ptmx' node into /dev/pts and use the inode of the 'ptmx'
node to identify the superblock and hence the devpts instance.  This patch
adds ability for the kernel to internally create the [ptmx, c, 5:2] device
when mounting devpts filesystem.  Since the ptmx node in devpts is new and
may surprise some userspace scripts, the default permissions for the new
node is 0000.  These permissions can be changed either using chmod or by
remounting with the new '-o ptmxmode=0666' mount option.

Changelog[v5]:
	- [Serge Hallyn bugfix]: Letting new_inode() assign inode number to
	  ptmx can collide with hand-assigning inode numbers to ptys. So,
	  hand-assign specific inode number to ptmx node also.
	- [Serge Hallyn]: Maybe safer to grab root dentry mutex while creating
	  ptmx node
	- [Bugfix with Serge Hallyn] Replace lookup_one_len() in mknod_ptmx()
	  wih d_alloc_name() (lookup during ->get_sb() locks up system). To
	  simplify patchset, fold the ptmx_dentry patch into this.

Changelog[v4]:
	- Change default permissions of pts/ptmx node to 0000.
	- Move code for ptmxmode under #ifdef CONFIG_DEVPTS_MULTIPLE_INSTANCES.

Changelog[v3]:
	- Rename ptmx_mode to ptmxmode (for consistency with 'newinstance')

Changelog[v2]:
	- [H. Peter Anvin] Remove mknod() system call support and create the
	  ptmx node internally.

Changelog[v1]:
	- Earlier version of this patch enabled creating /dev/pts/tty as
	  well. As pointed out by Al Viro and H. Peter Anvin, that is not
	  really necessary.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:36 -08:00
Sukadev Bhattiprolu 53af8ee409 Extract option parsing to new function
Move code to parse mount options into a separate function so it can
(later) be shared between mount and remount operations.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:35 -08:00
Sukadev Bhattiprolu 31af0abbda Per-mount 'config' object
With support for multiple mounts of devpts, the 'config' structure really
represents per-mount options rather than config parameters. Rename 'config'
structure to 'pts_mount_opts' and store it in the super-block.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:35 -08:00
Sukadev Bhattiprolu e76b7c01e5 Per-mount allocated_ptys
To enable multiple mounts of devpts, 'allocated_ptys' must be a per-mount
variable rather than a global variable.  Move 'allocated_ptys' into the
super_block's s_fs_info.

Changelog[v2]:
	Define and use DEVPTS_SB() wrapper.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:35 -08:00
Sukadev Bhattiprolu 59e55e6cf8 Remove devpts_root global
Remove the 'devpts_root' global variable and find the root dentry using
the super_block. The super-block can be found from the device inode, using
the new wrapper, pts_sb_from_inode().

Changelog: This patch is based on an earlier patchset from Serge Hallyn
	   and Matt Helsley.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02 10:19:35 -08:00
Linus Torvalds b58602a4ba Merge branch 'for-linus' of 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: (34 commits)
  nfsd race fixes: jfs
  nfsd race fixes: reiserfs
  nfsd race fixes: ext4
  nfsd race fixes: ext3
  nfsd race fixes: ext2
  nfsd/create race fixes, infrastructure
  filesystem notification: create fs/notify to contain all fs notification
  fs/block_dev.c: __read_mostly improvement and sb_is_blkdev_sb utilization
  kill ->dir_notify()
  filp_cachep can be static in fs/file_table.c
  fix f_count description in Documentation/filesystems/files.txt
  make INIT_FS use the __RW_LOCK_UNLOCKED initialization
  take init_fs to saner place
  kill vfs_permission
  pass a struct path * to may_open
  kill walk_init_root
  remove incorrect comment in inode_permission
  expand some comments (d_path / seq_path)
  correct wrong function name of d_put in kernel document and source comment
  fix switch_names() breakage in short-to-short case
  ...
2008-12-31 15:57:56 -08:00
Dave Kleikamp 1f3403fa64 nfsd race fixes: jfs
jfs version of Al Viro's nfsd race patches

Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:44 -05:00
Al Viro c1eaa26b67 nfsd race fixes: reiserfs
... and the same for reiserfs.  The difference here is that we need
insert_inode_locked4() to match iget5_locked().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:44 -05:00
Al Viro 6b38e842bb nfsd race fixes: ext4
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:44 -05:00
Al Viro c38012daa7 nfsd race fixes: ext3
ext3 analog of the previous patch

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:44 -05:00
Al Viro 41080b5a24 nfsd race fixes: ext2
* make ext2_new_inode() put the inode into icache in locked state
* do not unlock until the inode is fully set up; otherwise nfsd
might pick it in half-baked state.
* make sure that ext2_new_inode() does *not* lead to two inodes with the
same inumber hashed at the same time; otherwise a bogus fhandle coming
from nfsd might race with inode creation:

nfsd: iget_locked() creates inode
nfsd: try to read from disk, block on that.
ext2_new_inode(): allocate inode with that inumber
ext2_new_inode(): insert it into icache, set it up and dirty
ext2_write_inode(): get the relevant part of inode table in cache,
set the entry for our inode (and start writing to disk)
nfsd: get CPU again, look into inode table, see nice and sane on-disk
inode, set the in-core inode from it

oops - we have two in-core inodes with the same inumber live in icache,
both used for IO.  Welcome to fs corruption...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:43 -05:00
Al Viro 261bca86ed nfsd/create race fixes, infrastructure
new helpers - insert_inode_locked() and insert_inode_locked4().
Hash new inode, making sure that there's no such inode in icache
already.  If there is and it does not end up unhashed (as would
happen if we have nfsd trying to resolve a bogus fhandle), fail.
Otherwise insert our inode into hash and succeed.

In either case have i_state set to new+locked; cleanup ends up
being simpler with such calling conventions.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:43 -05:00
Eric Paris 272eb01485 filesystem notification: create fs/notify to contain all fs notification
Creating a generic filesystem notification interface, fsnotify, which will be
used by inotify, dnotify, and eventually fanotify is really starting to
clutter the fs directory.  This patch simply moves inotify and dnotify into
fs/notify/inotify and fs/notify/dnotify respectively to make both current fs/
and future notification tidier.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:43 -05:00
Denis ChengRq c2acf7b908 fs/block_dev.c: __read_mostly improvement and sb_is_blkdev_sb utilization
- iget5_locked in bdget really needs blockdev_superblock, instead of
  bd_mnt, so bd_mnt could be just a local variable;

- blockdev_superblock really needs __read_mostly, while local var bd_mnt
  not;

- make use of sb_is_blkdev_sb in bd_forget, instead of direct reference
  to blockdev_superblock.

Signed-off-by: Denis ChengRq <crquan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:43 -05:00
Al Viro 6badd79bd0 kill ->dir_notify()
Remove the hopelessly misguided ->dir_notify().  The only instance (cifs)
has been broken by design from the very beginning; the objects it creates
are never destroyed, keep references to struct file they can outlive, nothing
that could possibly evict them exists on close(2) path *and* no locking
whatsoever is done to prevent races with close(), should the previous, er,
deficiencies someday be dealt with.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:43 -05:00
Eric Dumazet b6b3fdead2 filp_cachep can be static in fs/file_table.c
Instead of creating the "filp" kmem_cache in vfs_caches_init(),
we can do it a litle be later in files_init(), so that filp_cachep
is static to fs/file_table.c

Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-31 18:07:42 -05:00