use binary search to find cache index that corresponds to readdir
postion.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

Use kmem_cache_zalloc() instead of kmem_cache_alloc() with flag GFP_ZERO.
Signed-off-by: NGeliang Tang <geliangtang@163.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

If dentry has no lease, ceph_d_revalidate() previously return 0.
This causes VFS to invalidate the dentry and create a new dentry
for later lookup. Invalidating a dentry also detach any underneath
mount points. So mount point inside cephfs can disapear mystically
(even the mount point is not modified by other hosts).

The fix is using lookup request to revalidate dentry without lease.
This can partly solve the mount points disapear issue (as long as
the mount point is not modified by other hosts)
Signed-off-by: NYan, Zheng <zyan@redhat.com>

use vfs helper dget_parent() instead
Signed-off-by: NYan, Zheng <zyan@redhat.com>

When security is enabled, security module can call filesystem's
getxattr/setxattr callbacks during d_instantiate(). For cephfs,
d_instantiate() is usually called by MDS' dispatch thread, while
handling MDS reply. If the MDS reply does not include xattrs and
corresponding caps, getxattr/setxattr need to send a new request
to MDS and waits for the reply. This makes MDS' dispatch sleep,
nobody handles later MDS replies.

The fix is make sure lookup/atomic_open reply include xattrs and
corresponding caps. So getxattr can be handled by cached xattrs.
This requires some modification to both MDS and request message.
(Client tells MDS what caps it wants; MDS encodes proper caps in
the reply)

Smack security module may call setxattr during d_instantiate().
Unlike getxattr, we can't force MDS to issue CEPH_CAP_XATTR_EXCL
to us. So just make setxattr return error when called by MDS'
dispatch thread.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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: NAl Viro <viro@zeniv.linux.org.uk>

Previously our dcache readdir code relies on that child dentries in
directory dentry's d_subdir list are sorted by dentry's offset in
descending order. When adding dentries to the dcache, if a dentry
already exists, our readdir code moves it to head of directory
dentry's d_subdir list. This design relies on dcache internals.
Al Viro suggests using ncpfs's approach: keeping array of pointers
to dentries in page cache of directory inode. the validity of those
pointers are presented by directory inode's complete and ordered
flags. When a dentry gets pruned, we clear directory inode's complete
flag in the d_prune() callback. Before moving a dentry to other
directory, we clear the ordered flag for both old and new directory.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

GFP_NOFS memory allocation is required for page writeback path.
But there is no need to use GFP_NOFS in syscall path and readpage
path
Signed-off-by: NYan, Zheng <zyan@redhat.com>

fsync() on directory should flush dirty caps and wait for any
uncommitted directory opertions to commit. But ceph_dir_fsync()
only waits for uncommitted directory opertions.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

No need to bifurcate wait now that we've got ceph_timeout_jiffies().
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NAlex Elder <elder@linaro.org>
Reviewed-by: NYan, Zheng <zyan@redhat.com>

There are currently three libceph-level timeouts that the user can
specify on mount: mount_timeout, osd_idle_ttl and osdkeepalive.  All of
these are in seconds and no checking is done on user input: negative
values are accepted, we multiply them all by HZ which may or may not
overflow, arbitrarily large jiffies then get added together, etc.

There is also a bug in the way mount_timeout=0 is handled.  It's
supposed to mean "infinite timeout", but that's not how wait.h APIs
treat it and so __ceph_open_session() for example will busy loop
without much chance of being interrupted if none of ceph-mons are
there.

Fix all this by verifying user input, storing timeouts capped by
msecs_to_jiffies() in jiffies and using the new ceph_timeout_jiffies()
helper for all user-specified waits to handle infinite timeouts
correctly.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NAlex Elder <elder@linaro.org>

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

Signed-off-by: NYan, Zheng <zyan@redhat.com>

Currently, there is no check for the kstrdup() for r_path2,
r_path1 and snapdir_name as various locations as there is a
possibility of failure during memory pressure. Therefore,
returning ENOMEM where the checks have been missed.
Signed-off-by: NSanidhya Kashyap <sanidhya.gatech@gmail.com>
Signed-off-by: NYan, Zheng <zyan@redhat.com>

return type of wait_for_completion_timeout is unsigned long not int. An
appropriately named unsigned long is added and the assignment fixed up.
Signed-off-by: NNicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Signed-off-by: NYan, Zheng <zyan@redhat.com>

that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Convert the following where appropriate:

 (1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry).

 (2) S_ISREG(dentry->d_inode) to d_is_reg(dentry).

 (3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry).  This is actually more
     complicated than it appears as some calls should be converted to
     d_can_lookup() instead.  The difference is whether the directory in
     question is a real dir with a ->lookup op or whether it's a fake dir with
     a ->d_automount op.

In some circumstances, we can subsume checks for dentry->d_inode not being
NULL into this, provided we the code isn't in a filesystem that expects
d_inode to be NULL if the dirent really *is* negative (ie. if we're going to
use d_inode() rather than d_backing_inode() to get the inode pointer).

Note that the dentry type field may be set to something other than
DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS
manages the fall-through from a negative dentry to a lower layer.  In such a
case, the dentry type of the negative union dentry is set to the same as the
type of the lower dentry.

However, if you know d_inode is not NULL at the call site, then you can use
the d_is_xxx() functions even in a filesystem.

There is one further complication: a 0,0 chardev dentry may be labelled
DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE.  Strictly, this was
intended for special directory entry types that don't have attached inodes.

The following perl+coccinelle script was used:

use strict;

my @callers;
open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') ||
    die "Can't grep for S_ISDIR and co. callers";
@callers = <$fd>;
close($fd);
unless (@callers) {
    print "No matches\n";
    exit(0);
}

my @cocci = (
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISLNK(E->d_inode->i_mode)',
    '+ d_is_symlink(E)',
    '',
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISDIR(E->d_inode->i_mode)',
    '+ d_is_dir(E)',
    '',
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISREG(E->d_inode->i_mode)',
    '+ d_is_reg(E)' );

my $coccifile = "tmp.sp.cocci";
open($fd, ">$coccifile") || die $coccifile;
print($fd "$_\n") || die $coccifile foreach (@cocci);
close($fd);

foreach my $file (@callers) {
    chomp $file;
    print "Processing ", $file, "\n";
    system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 ||
	die "spatch failed";
}

[AV: overlayfs parts skipped]
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

When we receives traceless reply for request that created new inode,
we re-send a lookup request to MDS get information of the newly created
inode. (VFS expects FS' callback return an inode in create case)
This breaks one request into two requests. Other client may modify or
move to the new inode in the middle.

When the race happens, ceph_handle_notrace_create() unconditionally
links the dentry for 'create' operation to the inode returned by lookup.
This may confuse VFS when the inode is a directory (VFS does not allow
multiple linkages for directory inode).

This patch makes ceph_handle_notrace_create() when it detect a race.
This event should be rare and it happens only when we talk to old MDS.
Recent MDS does not send traceless reply for request that creates new
inode.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

Signed-off-by: NYan, Zheng <zyan@redhat.com>

remove all unsupported operations from {inode,file}_operations.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

mksnap reply only contain 'target', does not contain 'dentry'. So
it's wrong to use req->r_reply_info.head->is_dentry to detect traceless
reply.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>

After creating/deleting/renaming file, offsets of sibling dentries may
change. So we can not use cached dentries to satisfy readdir. But we can
still use the cached dentries to conclude -ENOENT for lookup.

This patch introduces a new inode flag indicating if child dentries are
ordered. The flag is set at the same time marking a directory complete.
After creating/deleting/renaming file, we clear the flag on directory
inode. This prevents ceph_readdir() from using cached dentries to satisfy
readdir syscall.
Signed-off-by: NYan, Zheng <zyan@redhat.com>

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

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

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

Current code set new file/directory's initial ACL in a non-atomic
manner.
Client first sends request to MDS to create new file/directory, then set
the initial ACL after the new file/directory is successfully created.

The fix is include the initial ACL in create/mkdir/mknod MDS requests.
So MDS can handle creating file/directory and setting the initial ACL in
one request.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>

Now that d_invalidate always succeeds it is not longer necessary or
desirable to hard code d_drop calls into filesystem specific
d_revalidate implementations.

Remove the unnecessary d_drop calls and rely on d_invalidate
to drop the dentries.  Using d_invalidate ensures that paths
to mount points will not be dropped.
Reviewed-by: NMiklos Szeredi <miklos@szeredi.hu>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

When creating a file, ceph_set_dentry_offset() puts the new dentry
at the end of directory's d_subdirs, then set the dentry's offset
based on directory's max offset. The offset does not reflect the
real postion of the dentry in directory. Later readdir reply from
MDS may change the dentry's position/offset. This inconsistency
can cause missing/duplicate entries in readdir result if readdir
is partly satisfied by dcache_readdir().

The fix is clear directory's completeness after creating/renaming
file. It prevents later readdir from using dcache_readdir().

Fixes: http://tracker.ceph.com/issues/8025Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

skip dentries that were added before MDS issued FILE_SHARED to
client.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NSage Weil <sage@inktank.com>

Preallocate buffer for readdir reply. Limit number of entries in
readdir reply according to the buffer size.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

This is racy--we do not know whather d_parent has changed out from
underneath us because i_mutex is not held on the source inode's directory.

Also, taking this reference is useless.
Reported-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NSage Weil <sage@inktank.com>
Reviewed-by: NYan, Zheng <zheng.z.yan@intel.com>

This is just old_dir; no reason to abuse the dcache pointers.

Reported-by: Al Viro <viro.zeniv.linux.org.uk>
Signed-off-by: NSage Weil <sage@inktank.com>
Reviewed-by: NYan, Zheng <zheng.z.yan@intel.com>

If readdir 'frag' is adjusted, readdir 'offset' should be reset.
Otherwise some dentries may be lost when readdir and fragmenting
directory happen at the some.

Another way to fix this issue is let MDS adjust readdir 'frag'.
The code that handles MDS reply reset the readdir 'offset' if
the readdir reply is different than the requested one.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>

When changing readdir postion, fi->next_offset should be set to 0
if the new postion is not in the first dirfrag.
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NAlex Elder <elder@linaro.org>

Comparing offset with inode->i_sb->s_maxbytes doesn't make sense for
directory. For a fragmented directory, offset (frag_t, off) can be
larger than inode->i_sb->s_maxbytes.

At the very beginning of ceph_dir_llseek(), local variable old_offset
is initialized to parameter offset. This doesn't make sense neither.
Old_offset should be ceph_make_fpos(fi->frag, fi->next_offset).
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: NAlex Elder <elder@linaro.org>

If directory is fragmented, readdir() read its dirfrags one by one.
After reading all dirfrags, the corresponding dentries are sorted in
(frag_t, off) order in the dcache. If dentries of a directory are all
cached, __dcache_readdir() can use the cached dentries to satisfy
readdir syscall. But when checking if a given dentry is after the
position of readdir, __dcache_readdir() compares numerical value of
frag_t directly. This is wrong, it should use ceph_frag_compare().
Signed-off-by: NYan, Zheng <zheng.z.yan@intel.com>