reiserfs: convert to ctime accessor functions

In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-70-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs: port inode_owner_or_capable() to mnt_idmap

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>

fs: port ->fileattr_set() to pass mnt_idmap

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>

reiserfs: convert to fileattr

Use the fileattr API to let the VFS handle locking, permission checking and
conversion.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: Jan Kara <jack@suse.cz>

inode: make init and permission helpers idmapped mount aware

The inode_owner_or_capable() helper determines whether the caller is the
owner of the inode or is capable with respect to that inode. Allow it to
handle idmapped mounts. If the inode is accessed through an idmapped
mount it according to the mount's user namespace. Afterwards the checks
are identical to non-idmapped mounts. If the initial user namespace is
passed nothing changes so non-idmapped mounts will see identical
behavior as before.

Similarly, allow the inode_init_owner() helper to handle idmapped
mounts. It initializes a new inode on idmapped mounts by mapping the
fsuid and fsgid of the caller from the mount's user namespace. If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.

Link: https://lore.kernel.org/r/20210121131959.646623-7-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

reiserfs: clean up several indentation issues

There are several places where code is indented incorrectly. Fix these.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200325135018.113431-1-colin.king@canonical.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vfs: create a generic checking and prep function for FS_IOC_SETFLAGS

Create a generic function to check incoming FS_IOC_SETFLAGS flag values
and later prepare the inode for updates so that we can standardize the
implementations that follow ext4's flag values.

Note that the efivarfs implementation no longer fails a no-op SETFLAGS
without CAP_LINUX_IMMUTABLE since that's the behavior in ext*.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>

reiserfs: Remove i_attrs_to_sd_attrs()

Now that all places setting inode->i_flags that should be reflected in
on-disk flags are gone, we can remove i_attrs_to_sd_attrs() call.

Signed-off-by: Jan Kara <jack@suse.cz>

fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps

CURRENT_TIME_SEC is not y2038 safe. current_time() will
be transitioned to use 64 bit time along with vfs in a
separate patch.
There is no plan to transistion CURRENT_TIME_SEC to use
y2038 safe time interfaces.

current_time() will also be extended to use superblock
range checking parameters when range checking is introduced.

This works because alloc_super() fills in the the s_time_gran
in super block to NSEC_PER_SEC.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

reiserfs: open-code reiserfs_mutex_lock_safe() in reiserfs_unpack()

... and have it use inode_lock()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized. And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special. They are
not.

The changes are pretty straight-forward:

- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

- page_cache_get() -> get_page();

- page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

wrappers for ->i_mutex access

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/reiserfs: use linux/uaccess.h

Fix checkpatch warning

WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>

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>

reiserfs: cleanup, remove leading whitespace from labels

This patch moves reiserfs closer to adhering to the style rules by
removing leading whitespace from labels.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>

reiserfs: cleanup, reformat comments to normal kernel style

This patch reformats comments in the reiserfs code to fit in 80 columns and
to follow the style rules.

There is no functional change but it helps make my eyes bleed less.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>

reiserfs: locking, handle nested locks properly

The reiserfs write lock replaced the BKL and uses similar semantics.

Frederic's locking code makes a distinction between when the lock is nested
and when it's being acquired/released, but I don't think that's the right
distinction to make.

The right distinction is between the lock being released at end-of-use and
the lock being released for a schedule. The unlock should return the depth
and the lock should restore it, rather than the other way around as it is now.

This patch implements that and adds a number of places where the lock
should be dropped.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>

new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

move private bits of reiserfs_fs.h to fs/reiserfs/reiserfs.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

vfs: mnt_drop_write_file()

new helper (wrapper around mnt_drop_write()) to be used in pair with
mnt_want_write_file().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

switch a bunch of places to mnt_want_write_file()

it's both faster (in case when file has been opened for write) and cleaner.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

userns: rename is_owner_or_cap to inode_owner_or_capable

And give it a kernel-doc comment.

[akpm@linux-foundation.org: btrfs changed in linux-next]
Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

reiserfs: fix inode mutex - reiserfs lock misordering

reiserfs_unpack() locks the inode mutex with reiserfs_mutex_lock_safe()
to protect against reiserfs lock dependency. However this protection
requires to have the reiserfs lock to be locked.

This is the case if reiserfs_unpack() is called by reiserfs_ioctl but
not from reiserfs_quota_on() when it tries to unpack tails of quota
files.

Fix the ordering of the two locks in reiserfs_unpack() to fix this
issue.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reported-by: Markus Gapp <markus.gapp@gmx.net>
Reported-by: Jan Kara <jack@suse.cz>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: <stable@kernel.org> [2.6.36.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

BKL: remove extraneous #include <smp_lock.h>

The big kernel lock has been removed from all these files at some point,
leaving only the #include.

Remove this too as a cleanup.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs: kill block_prepare_write

__block_write_begin and block_prepare_write are identical except for slightly
different calling conventions. Convert all callers to the __block_write_begin
calling conventions and drop block_prepare_write.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

reiserfs: fix unwanted reiserfs lock recursion

Prevent from recursively locking the reiserfs lock in reiserfs_unpack()
because we may call journal_begin() that requires the lock to be taken
only once, otherwise it won't be able to release the lock while taking
other mutexes, ending up in inverted dependencies between the journal
mutex and the reiserfs lock for example.

This fixes:

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.35.4.4a #3
-------------------------------------------------------
lilo/1620 is trying to acquire lock:
(&journal->j_mutex){+.+...}, at: [<d0325bff>] do_journal_begin_r+0x7f/0x340 [reiserfs]

but task is already holding lock:
(&REISERFS_SB(s)->lock){+.+.+.}, at: [<d032a278>] reiserfs_write_lock+0x28/0x40 [reiserfs]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&REISERFS_SB(s)->lock){+.+.+.}:
[<c10562b7>] lock_acquire+0x67/0x80
[<c12facad>] __mutex_lock_common+0x4d/0x410
[<c12fb0c8>] mutex_lock_nested+0x18/0x20
[<d032a278>] reiserfs_write_lock+0x28/0x40 [reiserfs]
[<d0325c06>] do_journal_begin_r+0x86/0x340 [reiserfs]
[<d0325f77>] journal_begin+0x77/0x140 [reiserfs]
[<d0315be4>] reiserfs_remount+0x224/0x530 [reiserfs]
[<c10b6a20>] do_remount_sb+0x60/0x110
[<c10cee25>] do_mount+0x625/0x790
[<c10cf014>] sys_mount+0x84/0xb0
[<c12fca3d>] syscall_call+0x7/0xb

-> #0 (&journal->j_mutex){+.+...}:
[<c10560f6>] __lock_acquire+0x1026/0x1180
[<c10562b7>] lock_acquire+0x67/0x80
[<c12facad>] __mutex_lock_common+0x4d/0x410
[<c12fb0c8>] mutex_lock_nested+0x18/0x20
[<d0325bff>] do_journal_begin_r+0x7f/0x340 [reiserfs]
[<d0325f77>] journal_begin+0x77/0x140 [reiserfs]
[<d0326271>] reiserfs_persistent_transaction+0x41/0x90 [reiserfs]
[<d030d06c>] reiserfs_get_block+0x22c/0x1530 [reiserfs]
[<c10db9db>] __block_prepare_write+0x1bb/0x3a0
[<c10dbbe6>] block_prepare_write+0x26/0x40
[<d030b738>] reiserfs_prepare_write+0x88/0x170 [reiserfs]
[<d03294d6>] reiserfs_unpack+0xe6/0x120 [reiserfs]
[<d0329782>] reiserfs_ioctl+0x272/0x320 [reiserfs]
[<c10c3188>] vfs_ioctl+0x28/0xa0
[<c10c3bbd>] do_vfs_ioctl+0x32d/0x5c0
[<c10c3eb3>] sys_ioctl+0x63/0x70
[<c12fca3d>] syscall_call+0x7/0xb

other info that might help us debug this:

2 locks held by lilo/1620:
#0: (&sb->s_type->i_mutex_key#8){+.+.+.}, at: [<d032945a>] reiserfs_unpack+0x6a/0x120 [reiserfs]
#1: (&REISERFS_SB(s)->lock){+.+.+.}, at: [<d032a278>] reiserfs_write_lock+0x28/0x40 [reiserfs]

stack backtrace:
Pid: 1620, comm: lilo Not tainted 2.6.35.4.4a #3
Call Trace:
[<c10560f6>] __lock_acquire+0x1026/0x1180
[<c10562b7>] lock_acquire+0x67/0x80
[<c12facad>] __mutex_lock_common+0x4d/0x410
[<c12fb0c8>] mutex_lock_nested+0x18/0x20
[<d0325bff>] do_journal_begin_r+0x7f/0x340 [reiserfs]
[<d0325f77>] journal_begin+0x77/0x140 [reiserfs]
[<d0326271>] reiserfs_persistent_transaction+0x41/0x90 [reiserfs]
[<d030d06c>] reiserfs_get_block+0x22c/0x1530 [reiserfs]
[<c10db9db>] __block_prepare_write+0x1bb/0x3a0
[<c10dbbe6>] block_prepare_write+0x26/0x40
[<d030b738>] reiserfs_prepare_write+0x88/0x170 [reiserfs]
[<d03294d6>] reiserfs_unpack+0xe6/0x120 [reiserfs]
[<d0329782>] reiserfs_ioctl+0x272/0x320 [reiserfs]
[<c10c3188>] vfs_ioctl+0x28/0xa0
[<c10c3bbd>] do_vfs_ioctl+0x32d/0x5c0
[<c10c3eb3>] sys_ioctl+0x63/0x70
[<c12fca3d>] syscall_call+0x7/0xb

Reported-by: Jarek Poplawski <jarkao2@gmail.com>
Tested-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: All since 2.6.32 <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

reiserfs: fix dependency inversion between inode and reiserfs mutexes

The reiserfs mutex already depends on the inode mutex, so we can't lock
the inode mutex in reiserfs_unpack() without using the safe locking API,
because reiserfs_unpack() is always called with the reiserfs mutex locked.

This fixes:

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.35c #13
-------------------------------------------------------
lilo/1606 is trying to acquire lock:
(&sb->s_type->i_mutex_key#8){+.+.+.}, at: [<d0329450>] reiserfs_unpack+0x60/0x110 [reiserfs]

but task is already holding lock:
(&REISERFS_SB(s)->lock){+.+.+.}, at: [<d032a268>] reiserfs_write_lock+0x28/0x40 [reiserfs]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&REISERFS_SB(s)->lock){+.+.+.}:
[<c1056347>] lock_acquire+0x67/0x80
[<c12f083d>] __mutex_lock_common+0x4d/0x410
[<c12f0c58>] mutex_lock_nested+0x18/0x20
[<d032a268>] reiserfs_write_lock+0x28/0x40 [reiserfs]
[<d0329e9a>] reiserfs_lookup_privroot+0x2a/0x90 [reiserfs]
[<d0316b81>] reiserfs_fill_super+0x941/0xe60 [reiserfs]
[<c10b7d17>] get_sb_bdev+0x117/0x170
[<d0313e21>] get_super_block+0x21/0x30 [reiserfs]
[<c10b74ba>] vfs_kern_mount+0x6a/0x1b0
[<c10b7659>] do_kern_mount+0x39/0xe0
[<c10cebe0>] do_mount+0x340/0x790
[<c10cf0b4>] sys_mount+0x84/0xb0
[<c12f25cd>] syscall_call+0x7/0xb

-> #0 (&sb->s_type->i_mutex_key#8){+.+.+.}:
[<c1056186>] __lock_acquire+0x1026/0x1180
[<c1056347>] lock_acquire+0x67/0x80
[<c12f083d>] __mutex_lock_common+0x4d/0x410
[<c12f0c58>] mutex_lock_nested+0x18/0x20
[<d0329450>] reiserfs_unpack+0x60/0x110 [reiserfs]
[<d0329772>] reiserfs_ioctl+0x272/0x320 [reiserfs]
[<c10c3228>] vfs_ioctl+0x28/0xa0
[<c10c3c5d>] do_vfs_ioctl+0x32d/0x5c0
[<c10c3f53>] sys_ioctl+0x63/0x70
[<c12f25cd>] syscall_call+0x7/0xb

other info that might help us debug this:

1 lock held by lilo/1606:
#0: (&REISERFS_SB(s)->lock){+.+.+.}, at: [<d032a268>] reiserfs_write_lock+0x28/0x40 [reiserfs]

stack backtrace:
Pid: 1606, comm: lilo Not tainted 2.6.35c #13
Call Trace:
[<c1056186>] __lock_acquire+0x1026/0x1180
[<c1056347>] lock_acquire+0x67/0x80
[<c12f083d>] __mutex_lock_common+0x4d/0x410
[<c12f0c58>] mutex_lock_nested+0x18/0x20
[<d0329450>] reiserfs_unpack+0x60/0x110 [reiserfs]
[<d0329772>] reiserfs_ioctl+0x272/0x320 [reiserfs]
[<c10c3228>] vfs_ioctl+0x28/0xa0
[<c10c3c5d>] do_vfs_ioctl+0x32d/0x5c0
[<c10c3f53>] sys_ioctl+0x63/0x70
[<c12f25cd>] syscall_call+0x7/0xb

Reported-by: Jarek Poplawski <jarkao2@gmail.com>
Tested-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: <stable@kernel.org> [2.6.32 and later]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

reiserfs: Fix unreachable statement

Stanse found an unreachable statement in reiserfs_ioctl. There is a
if followed by error assignment and `break' with no braces. Add the
braces so that we don't break every time, but only in error case,
so that REISERFS_IOC_SETVERSION actually works when it returns no
error.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Reiserfs <reiserfs-devel@vger.kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

kill-the-bkl/reiserfs: definitely drop the bkl from reiserfs_ioctl()

The reiserfs ioctl path doesn't need the big kernel lock anymore , now
that the filesystem synchronizes through its own lock.

We can then turn reiserfs_ioctl() into an unlocked_ioctl callback.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alexander Beregalov <a.beregalov@gmail.com>
Cc: Laurent Riffard <laurent.riffard@free.fr>
Cc: Thomas Gleixner <tglx@linutronix.de>

kill-the-bkl/reiserfs: always lock the ioctl path

Reiserfs uses the ioctl callback for its file operations, which means
that its ioctl path is still locked by the bkl, this was synchronizing
with the rest of the filsystem operations. We have changed that by
locking it with the new reiserfs lock but we do that only from the
compat_ioctl callback.

Fix that by locking reiserfs_ioctl() everytime.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alexander Beregalov <a.beregalov@gmail.com>
Cc: Laurent Riffard <laurent.riffard@free.fr>
Cc: Thomas Gleixner <tglx@linutronix.de>

reiserfs: kill-the-BKL

This patch is an attempt to remove the Bkl based locking scheme from
reiserfs and is intended.

It is a bit inspired from an old attempt by Peter Zijlstra:

http://lkml.indiana.edu/hypermail/linux/kernel/0704.2/2174.html

The bkl is heavily used in this filesystem to prevent from
concurrent write accesses on the filesystem.

Reiserfs makes a deep use of the specific properties of the Bkl:

- It can be acqquired recursively by a same task
- It is released on the schedule() calls and reacquired when schedule() returns

The two properties above are a roadmap for the reiserfs write locking so it's
very hard to simply replace it with a common mutex.

- We need a recursive-able locking unless we want to restructure several blocks
of the code.
- We need to identify the sites where the bkl was implictly relaxed
(schedule, wait, sync, etc...) so that we can in turn release and
reacquire our new lock explicitly.
Such implicit releases of the lock are often required to let other
resources producer/consumer do their job or we can suffer unexpected
starvations or deadlocks.

So the new lock that replaces the bkl here is a per superblock mutex with a
specific property: it can be acquired recursively by a same task, like the
bkl.

For such purpose, we integrate a lock owner and a lock depth field on the
superblock information structure.

The first axis on this patch is to turn reiserfs_write_(un)lock() function
into a wrapper to manage this mutex. Also some explicit calls to
lock_kernel() have been converted to reiserfs_write_lock() helpers.

The second axis is to find the important blocking sites (schedule...(),
wait_on_buffer(), sync_dirty_buffer(), etc...) and then apply an explicit
release of the write lock on these locations before blocking. Then we can
safely wait for those who can give us resources or those who need some.
Typically this is a fight between the current writer, the reiserfs workqueue
(aka the async commiter) and the pdflush threads.

The third axis is a consequence of the second. The write lock is usually
on top of a lock dependency chain which can include the journal lock, the
flush lock or the commit lock. So it's dangerous to release and trying to
reacquire the write lock while we still hold other locks.

This is fine with the bkl:

T1 T2

lock_kernel()
mutex_lock(A)
unlock_kernel()
// do something
lock_kernel()
mutex_lock(A) -> already locked by T1
schedule() (and then unlock_kernel())
lock_kernel()
mutex_unlock(A)
....

This is not fine with a mutex:

T1 T2

mutex_lock(write)
mutex_lock(A)
mutex_unlock(write)
// do something
mutex_lock(write)
mutex_lock(A) -> already locked by T1
schedule()

mutex_lock(write) -> already locked by T2
deadlock

The solution in this patch is to provide a helper which releases the write
lock and sleep a bit if we can't lock a mutex that depend on it. It's another
simulation of the bkl behaviour.

The last axis is to locate the fs callbacks that are called with the bkl held,
according to Documentation/filesystem/Locking.

Those are:

- reiserfs_remount
- reiserfs_fill_super
- reiserfs_put_super

Reiserfs didn't need to explicitly lock because of the context of these callbacks.
But now we must take care of that with the new locking.

After this patch, reiserfs suffers from a slight performance regression (for now).
On UP, a high volume write with dd reports an average of 27 MB/s instead
of 30 MB/s without the patch applied.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Bron Gondwana <brong@fastmail.fm>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
LKML-Reference: <1239070789-13354-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

reiserfs: strip trailing whitespace

This patch strips trailing whitespace from the reiserfs code.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

reiserfs: unpack tails on quota files

Quota files cannot have tails because quota_write and quota_read functions do
not support them. So far when quota files did have tail, we just refused to
turn quotas on it. Sadly this check has been wrong and so there are now
plenty installations where quota files don't have NOTAIL flag set and so now
after fixing the check, they suddently fail to turn quotas on. Since it's
easy to unpack the tail from kernel, do this from reiserfs_quota_on() which
solves the problem and is generally nicer to users anyway.

Signed-off-by: Jan Kara <jack@suse.cz>
Reported-by: <urhausen@urifabi.net>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[PATCH] r/o bind mounts: elevate write count for ioctls()

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>

Forbid user to change file flags on quota files

Forbid user from changing file flags on quota files. User has no bussiness
in playing with these flags when quota is on. Furthermore there is a
remote possibility of deadlock due to a lock inversion between quota file's
i_mutex and transaction's start (i_mutex for quota file is locked only when
trasaction is started in quota operations) in ext3 and ext4.

Signed-off-by: Jan Kara <jack@suse.cz>
Cc: LIOU Payphone <lioupayphone@gmail.com>
Cc: <linux-ext4@vger.kernel.org>
Acked-by: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

reiserfs: convert to new aops

Convert reiserfs to new aops

Signed-off-by: Vladimir Saveliev <vs@namesys.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid check

Introduce is_owner_or_cap() macro in fs.h, and convert over relevant
users to it. This is done because we want to avoid bugs in the future
where we check for only effective fsuid of the current task against a
file's owning uid, without simultaneously checking for CAP_FOWNER as
well, thus violating its semantics.
[ XFS uses special macros and structures, and in general looked ...
untouchable, so we leave it alone -- but it has been looked over. ]

The (current->fsuid != inode->i_uid) check in generic_permission() and
exec_permission_lite() is left alone, because those operations are
covered by CAP_DAC_OVERRIDE and CAP_DAC_READ_SEARCH. Similarly operations
falling under the purview of CAP_CHOWN and CAP_LEASE are also left alone.

Signed-off-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Cc: Al Viro <viro@ftp.linux.org.uk>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[PATCH] struct path: convert reiserfs

Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] BLOCK: Move the ReiserFS device ioctl compat stuff to the ReiserFS driver [try #6]

Move the ReiserFS device ioctl compat stuff from fs/compat_ioctl.c to the
ReiserFS driver so that the ReiserFS header file doesn't need to be included.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

[PATCH] fix reiserfs lock inversion of bkl vs inode semaphore

The correct lock ordering is inode lock -> BKL

Signed-off-by: Chris Mason <mason@suse.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] capable/capability.h (fs/)

fs: Use <linux/capability.h> where capable() is used.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Acked-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_sem

This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.

Modified-by: Ingo Molnar <mingo@elte.hu>

(finished the conversion)

Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

reiserfs: run scripts/Lindent on reiserfs code

This was a pure indentation change, using:

scripts/Lindent fs/reiserfs/*.c include/linux/reiserfs_*.h

to make reiserfs match the regular Linux indentation style. As Jeff
Mahoney <jeffm@suse.com> writes:

The ReiserFS code is a mix of a number of different coding styles, sometimes
different even from line-to-line. Since the code has been relatively stable
for quite some time and there are few outstanding patches to be applied, it
is time to reformat the code to conform to the Linux style standard outlined
in Documentation/CodingStyle.

This patch contains the result of running scripts/Lindent against
fs/reiserfs/*.c and include/linux/reiserfs_*.h. There are places where the
code can be made to look better, but I'd rather keep those patches separate
so that there isn't a subtle by-hand hand accident in the middle of a huge
patch. To be clear: This patch is reformatting *only*.

A number of patches may follow that continue to make the code more consistent
with the Linux coding style.

Hans wasn't particularly enthusiastic about these patches, but said he
wouldn't really oppose them either.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] reiserfs: Check if attrs are enabled for attr ioctls

ReiserFS currently will allow the user to set/get attrs for files
regardless if they are enabled. The patch checks to see if they are
enabled, and returns -NOTTY if they are not.

ext[23] doesn't need this check because attrs are always enabled.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!