Need to drop cap reference before retry. Besides, it's better to
redo file write checks for each retry because we re-lock inode.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
startsync is a no-op, has been for years. Remove it.
Link: http://tracker.ceph.com/issues/20604
Signed-off-by: Yanhu Cao <gmayyyha@gmail.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
OSD has a configurable limitation of max write size. OSD return
error if write request size is larger than the limitation. For now,
set max write size to CEPH_MSG_MAX_DATA_LEN. It should be small
enough.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The old 'approaching max_size' code expects MDS set max_size to
'2 * reported_size'. This is no longer true. The new code reports
file size when half of previous max_size increment has been used.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Currently the ceph client doesn't respect the rlimit in fallocate. This
means that a user can allocate a file with size > RLIMIT_FSIZE. This
patch adds the call to inode_newsize_ok() to verify filesystem limits and
ulimits. This should make ceph successfully run xfstest generic/228.
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
lock transfers from myself and the long awaited -ENOSPC handling series
from Jeff. The former will allow rbd users to take advantage of
exclusive lock's built-in blacklist/break-lock functionality while
staying in control of who owns the lock. With the latter in place, we
will abort filesystem writes on -ENOSPC instead of having them block
indefinitely.
Beyond that we've got the usual pile of filesystem fixes from Zheng,
some refcount_t conversion patches from Elena and a patch for an
ancient open() flags handling bug from Alexander.
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Merge tag 'ceph-for-4.12-rc1' of git://github.com/ceph/ceph-client
Pull ceph updates from Ilya Dryomov:
"The two main items are support for disabling automatic rbd exclusive
lock transfers from myself and the long awaited -ENOSPC handling
series from Jeff.
The former will allow rbd users to take advantage of exclusive lock's
built-in blacklist/break-lock functionality while staying in control
of who owns the lock. With the latter in place, we will abort
filesystem writes on -ENOSPC instead of having them block
indefinitely.
Beyond that we've got the usual pile of filesystem fixes from Zheng,
some refcount_t conversion patches from Elena and a patch for an
ancient open() flags handling bug from Alexander"
* tag 'ceph-for-4.12-rc1' of git://github.com/ceph/ceph-client: (31 commits)
ceph: fix memory leak in __ceph_setxattr()
ceph: fix file open flags on ppc64
ceph: choose readdir frag based on previous readdir reply
rbd: exclusive map option
rbd: return ResponseMessage result from rbd_handle_request_lock()
rbd: kill rbd_is_lock_supported()
rbd: support updating the lock cookie without releasing the lock
rbd: store lock cookie
rbd: ignore unlock errors
rbd: fix error handling around rbd_init_disk()
rbd: move rbd_unregister_watch() call into rbd_dev_image_release()
rbd: move rbd_dev_destroy() call out of rbd_dev_image_release()
ceph: when seeing write errors on an inode, switch to sync writes
Revert "ceph: SetPageError() for writeback pages if writepages fails"
ceph: handle epoch barriers in cap messages
libceph: add an epoch_barrier field to struct ceph_osd_client
libceph: abort already submitted but abortable requests when map or pool goes full
libceph: allow requests to return immediately on full conditions if caller wishes
libceph: remove req->r_replay_version
ceph: make seeky readdir more efficient
...
There are many code paths opencoding kvmalloc. Let's use the helper
instead. The main difference to kvmalloc is that those users are
usually not considering all the aspects of the memory allocator. E.g.
allocation requests <= 32kB (with 4kB pages) are basically never failing
and invoke OOM killer to satisfy the allocation. This sounds too
disruptive for something that has a reasonable fallback - the vmalloc.
On the other hand those requests might fallback to vmalloc even when the
memory allocator would succeed after several more reclaim/compaction
attempts previously. There is no guarantee something like that happens
though.
This patch converts many of those places to kv[mz]alloc* helpers because
they are more conservative.
Link: http://lkml.kernel.org/r/20170306103327.2766-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> # Xen bits
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Andreas Dilger <andreas.dilger@intel.com> # Lustre
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> # KVM/s390
Acked-by: Dan Williams <dan.j.williams@intel.com> # nvdim
Acked-by: David Sterba <dsterba@suse.com> # btrfs
Acked-by: Ilya Dryomov <idryomov@gmail.com> # Ceph
Acked-by: Tariq Toukan <tariqt@mellanox.com> # mlx4
Acked-by: Leon Romanovsky <leonro@mellanox.com> # mlx5
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Santosh Raspatur <santosh@chelsio.com>
Cc: Hariprasad S <hariprasad@chelsio.com>
Cc: Yishai Hadas <yishaih@mellanox.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: "Yan, Zheng" <zyan@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The file open flags (O_foo) are platform specific and should never go
out to an interface that is not local to the system.
Unfortunately these flags have leaked out onto the wire in the cephfs
implementation. That lead to bogus flags getting transmitted on ppc64.
This patch converts the kernel view of flags to the ceph view of file
open flags.
Fixes: 124e68e74 ("ceph: file operations")
Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Currently, we don't have a real feedback mechanism in place for when we
start seeing buffered writeback errors. If writeback is failing, there
is nothing that prevents an application from continuing to dirty pages
that aren't being cleaned.
In the event that we're seeing write errors of any sort occur on an
inode, have the callback set a flag to force further writes to be
synchronous. When the next write succeeds, clear the flag to allow
buffered writeback to continue.
Since this is just a hint to the write submission mechanism, we only
take the i_ceph_lock when a lockless check shows that the flag needs to
be changed.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: "Yan, Zheng” <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Usually, when the osd map is flagged as full or the pool is at quota,
write requests just hang. This is not what we want for cephfs, where
it would be better to simply report -ENOSPC back to userland instead
of stalling.
If the caller knows that it will want an immediate error return instead
of blocking on a full or at-quota error condition then allow it to set a
flag to request that behavior.
Set that flag in ceph_osdc_new_request (since ceph.ko is the only caller),
and on any other write request from ceph.ko.
A later patch will deal with requests that were submitted before the new
map showing the full condition came in.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
CEPH_OSD_FLAG_ONDISK is set in account_request().
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
- ask for a commit reply instead of an ack reply in
__ceph_pool_perm_get()
- don't ask for both ack and commit replies in ceph_sync_write()
- since just only one reply is requested now, i_unsafe_writes list
will always be empty -- kill ceph_sync_write_wait() and go back to
a standard ->evict_inode()
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
struct ceph_mds_request has an r_locked_dir pointer, which is set to
indicate the parent inode and that its i_rwsem is locked. In some
critical places, we need to be able to indicate the parent inode to the
request handling code, even when its i_rwsem may not be locked.
Most of the code that operates on r_locked_dir doesn't require that the
i_rwsem be locked. We only really need it to handle manipulation of the
dcache. The rest (filling of the inode, updating dentry leases, etc.)
already has its own locking.
Add a new r_req_flags bit that indicates whether the parent is locked
when doing the request, and rename the pointer to "r_parent". For now,
all the places that set r_parent also set this flag, but that will
change in a later patch.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
__ceph_caps_mds_wanted() ignores caps from stale session. So the
return value of __ceph_caps_mds_wanted() can keep the same across
ceph_renew_caps(). This causes try_get_cap_refs() to keep calling
ceph_renew_caps(). The fix is ignore the session valid check for
the try_get_cap_refs() case. If session is stale, just let the
caps requester sleep.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
- a large rework of cephx auth code to cope with CONFIG_VMAP_STACK
(myself). Also fixed a deadlock caused by a bogus allocation on the
writeback path and authorize reply verification.
- a fix for long stalls during fsync (Jeff Layton). The client now
has a way to force the MDS log flush, leading to ~100x speedups in
some synthetic tests.
- a new [no]require_active_mds mount option (Zheng Yan). On mount, we
will now check whether any of the MDSes are available and bail rather
than block if none are. This check can be avoided by specifying the
"no" option.
- a couple of MDS cap handling fixes and a few assorted patches
throughout.
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Merge tag 'ceph-for-4.10-rc1' of git://github.com/ceph/ceph-client
Pull ceph updates from Ilya Dryomov:
"A varied set of changes:
- a large rework of cephx auth code to cope with CONFIG_VMAP_STACK
(myself). Also fixed a deadlock caused by a bogus allocation on the
writeback path and authorize reply verification.
- a fix for long stalls during fsync (Jeff Layton). The client now
has a way to force the MDS log flush, leading to ~100x speedups in
some synthetic tests.
- a new [no]require_active_mds mount option (Zheng Yan).
On mount, we will now check whether any of the MDSes are available
and bail rather than block if none are. This check can be avoided
by specifying the "no" option.
- a couple of MDS cap handling fixes and a few assorted patches
throughout"
* tag 'ceph-for-4.10-rc1' of git://github.com/ceph/ceph-client: (32 commits)
libceph: remove now unused finish_request() wrapper
libceph: always signal completion when done
ceph: avoid creating orphan object when checking pool permission
ceph: properly set issue_seq for cap release
ceph: add flags parameter to send_cap_msg
ceph: update cap message struct version to 10
ceph: define new argument structure for send_cap_msg
ceph: move xattr initialzation before the encoding past the ceph_mds_caps
ceph: fix minor typo in unsafe_request_wait
ceph: record truncate size/seq for snap data writeback
ceph: check availability of mds cluster on mount
ceph: fix splice read for no Fc capability case
ceph: try getting buffer capability for readahead/fadvise
ceph: fix scheduler warning due to nested blocking
ceph: fix printing wrong return variable in ceph_direct_read_write()
crush: include mapper.h in mapper.c
rbd: silence bogus -Wmaybe-uninitialized warning
libceph: no need to drop con->mutex for ->get_authorizer()
libceph: drop len argument of *verify_authorizer_reply()
libceph: verify authorize reply on connect
...
r_safe_completion is currently, and has always been, signaled only if
on-disk ack was requested. It's there for fsync and syncfs, which wait
for in-flight writes to flush - all data write requests set ONDISK.
However, the pool perm check code introduced in 4.2 sends a write
request with only ACK set. An unfortunately timed syncfs can then hang
forever: r_safe_completion won't be signaled because only an unsafe
reply was requested.
We could patch ceph_osdc_sync() to skip !ONDISK write requests, but
that is somewhat incomplete and yet another special case. Instead,
rename this completion to r_done_completion and always signal it when
the OSD client is done with the request, whether unsafe, safe, or
error. This is a bit cleaner and helps with the cancellation code.
Reported-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
When iov_iter type is ITER_PIPE, copy_page_to_iter() increases
the page's reference and add the page to a pipe_buffer. It also
set the pipe_buffer's ops to page_cache_pipe_buf_ops. The comfirm
callback in page_cache_pipe_buf_ops expects the page is from page
cache and uptodate, otherwise it return error.
For ceph_sync_read() case, pages are not from page cache. So we
can't call copy_page_to_iter() when iov_iter type is ITER_PIPE.
The fix is using iov_iter_get_pages_alloc() to allocate pages
for the pipe. (the code is similar to default_file_splice_read)
Signed-off-by: Yan, Zheng <zyan@redhat.com>
For readahead/fadvise cases, caller of ceph_readpages does not
hold buffer capability. Pages can be added to page cache while
there is no buffer capability. This can cause data integrity
issue.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Splice read/write implementation changed recently. When using
generic_file_splice_read(), iov_iter with type == ITER_PIPE is
passed to filesystem's read_iter callback. But ceph_sync_read()
can't serve ITER_PIPE iov_iter correctly (ITER_PIPE iov_iter
expects pages from page cache).
Fixing ceph_sync_read() requires a big patch. So use default
splice read callback for now.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
In case __ceph_do_getattr returns an error and the retry_op in
ceph_read_iter is not READ_INLINE, then it's possible to invoke
__free_page on a page which is NULL, this naturally leads to a crash.
This can happen when, for example, a process waiting on a MDS reply
receives sigterm.
Fix this by explicitly checking whether the page is set or not.
Cc: stable@vger.kernel.org # 3.19+
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Pull more vfs updates from Al Viro:
">rename2() work from Miklos + current_time() from Deepa"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: Replace current_fs_time() with current_time()
fs: Replace CURRENT_TIME_SEC with current_time() for inode timestamps
fs: Replace CURRENT_TIME with current_time() for inode timestamps
fs: proc: Delete inode time initializations in proc_alloc_inode()
vfs: Add current_time() api
vfs: add note about i_op->rename changes to porting
fs: rename "rename2" i_op to "rename"
vfs: remove unused i_op->rename
fs: make remaining filesystems use .rename2
libfs: support RENAME_NOREPLACE in simple_rename()
fs: support RENAME_NOREPLACE for local filesystems
ncpfs: fix unused variable warning
This call can fail if there are dirty pages. The preceding call to
filemap_write_and_wait_range() will normally remove dirty pages, but
as inode_lock() is not held over calls to ceph_direct_read_write(), it
could race with non-direct writes and pages could be dirtied
immediately after filemap_write_and_wait_range() returns
If there are dirty pages, they will be removed by the subsequent call
to truncate_inode_pages_range(), so having them here is not a problem.
If the 'ret' value is left holding an error, then in the async IO case
(aio_req is not NULL) the loop that would normally call
ceph_osdc_start_request() will see the error in 'ret' and abort all
requests. This doesn't seem like correct behaviour.
So use separate 'ret2' instead of overloading 'ret'.
Signed-off-by: NeilBrown <neilb@suse.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
current_fs_time() uses struct super_block* as an argument.
As per Linus's suggestion, this is changed to take struct
inode* as a parameter instead. This is because the function
is primarily meant for vfs inode timestamps.
Also the function was renamed as per Arnd's suggestion.
Change all calls to current_fs_time() to use the new
current_time() function instead. current_fs_time() will be
deleted.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
ceph_llseek does not correctly return NXIO errors because the 'out' path
always returns 'offset'.
Fixes: 06222e491e ("fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek")
Signed-off-by: Phil Turnbull <phil.turnbull@oracle.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Define new ceph_file_layout structure and rename old ceph_file_layout
to ceph_file_layout_legacy. This is preparation for adding namespace
to ceph_file_layout structure.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
->atomic_open() can be given an in-lookup dentry *or* a negative one
found in dcache. Use d_in_lookup() to tell one from another, rather
than d_unhashed().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
All other filesystems do not add dirty pages to fscache. They all
disable fscache when inode is opened for write. Only ceph adds
dirty pages to fscache, but the code is buggy.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
For the benefit of every single caller, take osdc instead of map.
Also, now that osdc->osdmap can't ever be NULL, drop the check.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Pull Ceph updates from Sage Weil:
"This changeset has a few main parts:
- Ilya has finished a huge refactoring effort to sync up the
client-side logic in libceph with the user-space client code, which
has evolved significantly over the last couple years, with lots of
additional behaviors (e.g., how requests are handled when cluster
is full and transitions from full to non-full).
This structure of the code is more closely aligned with userspace
now such that it will be much easier to maintain going forward when
behavior changes take place. There are some locking improvements
bundled in as well.
- Zheng adds multi-filesystem support (multiple namespaces within the
same Ceph cluster)
- Zheng has changed the readdir offsets and directory enumeration so
that dentry offsets are hash-based and therefore stable across
directory fragmentation events on the MDS.
- Zheng has a smorgasbord of bug fixes across fs/ceph"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (71 commits)
ceph: fix wake_up_session_cb()
ceph: don't use truncate_pagecache() to invalidate read cache
ceph: SetPageError() for writeback pages if writepages fails
ceph: handle interrupted ceph_writepage()
ceph: make ceph_update_writeable_page() uninterruptible
libceph: make ceph_osdc_wait_request() uninterruptible
ceph: handle -EAGAIN returned by ceph_update_writeable_page()
ceph: make fault/page_mkwrite return VM_FAULT_OOM for -ENOMEM
ceph: block non-fatal signals for fault/page_mkwrite
ceph: make logical calculation functions return bool
ceph: tolerate bad i_size for symlink inode
ceph: improve fragtree change detection
ceph: keep leaf frag when updating fragtree
ceph: fix dir_auth check in ceph_fill_dirfrag()
ceph: don't assume frag tree splits in mds reply are sorted
ceph: fix inode reference leak
ceph: using hash value to compose dentry offset
ceph: don't forbid marking directory complete after forward seek
ceph: record 'offset' for each entry of readdir result
ceph: define 'end/complete' in readdir reply as bit flags
...
When mds session gets killed, read/write operation may hang.
Client waits for Frw caps, but mds does not know what caps client
wants. To recover this, client sends an open request to mds. The
request will tell mds what caps client wants.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
If you specify ACK | ONDISK and set ->r_unsafe_callback, both
->r_callback and ->r_unsafe_callback(true) are called on ack. This is
very confusing. Redo this so that only one of them is called:
->r_unsafe_callback(true), on ack
->r_unsafe_callback(false), on commit
or
->r_callback, on ack|commit
Decode everything in decode_MOSDOpReply() to reduce clutter.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
finish_read(), its only user, uses it to get to hdr.data_len, which is
what ->r_result is set to on success. This gains us the ability to
safely call callbacks from contexts other than reply, e.g. map check.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The crux of this is getting rid of ceph_osdc_build_request(), so that
MOSDOp can be encoded not before but after calc_target() calculates the
actual target. Encoding now happens within ceph_osdc_start_request().
Also nuked is the accompanying bunch of pointers into the encoded
buffer that was used to update fields on each send - instead, the
entire front is re-encoded. If we want to support target->name_len !=
base->name_len in the future, there is no other way, because oid is
surrounded by other fields in the encoded buffer.
Encoding OSD ops and adding data items to the request message were
mixed together in osd_req_encode_op(). While we want to re-encode OSD
ops, we don't want to add duplicate data items to the message when
resending, so all call to ceph_osdc_msg_data_add() are factored out
into a new setup_request_data().
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Introduce ceph_osd_request_target, containing all mapping-related
fields of ceph_osd_request and calc_target() for calculating mappings
and populating it.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Currently ceph_object_id can hold object names of up to 100
(CEPH_MAX_OID_NAME_LEN) characters. This is enough for all use cases,
expect one - long rbd image names:
- a format 1 header is named "<imgname>.rbd"
- an object that points to a format 2 header is named "rbd_id.<imgname>"
We operate on these potentially long-named objects during rbd map, and,
for format 1 images, during header refresh. (A format 2 header name is
a small system-generated string.)
Lift this 100 character limit by making ceph_object_id be able to point
to an externally-allocated string. Apart from being able to work with
almost arbitrarily-long named objects, this allows us to reduce the
size of ceph_object_id from >100 bytes to 64 bytes.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The size of ->r_request and ->r_reply messages depends on the size of
the object name (ceph_object_id), while the size of ceph_osd_request is
fixed. Move message allocation into a separate function that would
have to be called after ceph_object_id and ceph_object_locator (which
is also going to become variable in size with RADOS namespaces) have
been filled in:
req = ceph_osdc_alloc_request(...);
<fill in req->r_base_oid>
<fill in req->r_base_oloc>
ceph_osdc_alloc_messages(req);
Signed-off-by: Ilya Dryomov <idryomov@gmail.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: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use kmem_cache_zalloc() instead of kmem_cache_alloc() with flag GFP_ZERO.
Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.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: Yan, Zheng <zyan@redhat.com>
CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_fs_time() instead.
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Pull Ceph updates from Sage Weil:
"The two main changes are aio support in CephFS, and a series that
fixes several issues in the authentication key timeout/renewal code.
On top of that are a variety of cleanups and minor bug fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
libceph: remove outdated comment
libceph: kill off ceph_x_ticket_handler::validity
libceph: invalidate AUTH in addition to a service ticket
libceph: fix authorizer invalidation, take 2
libceph: clear messenger auth_retry flag if we fault
libceph: fix ceph_msg_revoke()
libceph: use list_for_each_entry_safe
ceph: use i_size_{read,write} to get/set i_size
ceph: re-send AIO write request when getting -EOLDSNAP error
ceph: Asynchronous IO support
ceph: Avoid to propagate the invalid page point
ceph: fix double page_unlock() in page_mkwrite()
rbd: delete an unnecessary check before rbd_dev_destroy()
libceph: use list_next_entry instead of list_entry_next
ceph: ceph_frag_contains_value can be boolean
ceph: remove unused functions in ceph_frag.h
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>
Cap message from MDS can update i_size. In that case, we don't
hold i_mutex. So it's unsafe to directly access inode->i_size
while holding i_mutex.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
When receiving -EOLDSNAP from OSD, we need to re-send corresponding
write request. Due to locking issue, we can send new request inside
another OSD request's complete callback. So we use worker to re-send
request for AIO write.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
The basic idea of AIO support is simple, just call kiocb::ki_complete()
in OSD request's complete callback. But there are several special cases.
when IO span multiple objects, we need to wait until all OSD requests
are complete, then call kiocb::ki_complete(). Error handling in this case
is tricky too. For simplify, AIO both span multiple objects and extends
i_size are not allowed.
Another special case is check EOF for reading (other client can write to
the file and extend i_size concurrently). For simplify, the direct-IO/AIO
code path does do the check, fallback to normal syn read instead.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Both ceph_sync_direct_write and ceph_sync_read iterate iovec elements
one by one, send one OSD request for each iovec. This is sub-optimal,
We can combine serveral iovec into one page vector, and send an OSD
request for the whole page vector.
Signed-off-by: Zhu, Caifeng <zhucaifeng@unissoft-nj.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
parent inode is needed in creating new inode case. For ceph_open,
the target inode already exists.
Signed-off-by: Jianpeng Ma <jianpeng.ma@intel.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Pull more vfs updates from Al Viro:
"Assorted VFS fixes and related cleanups (IMO the most interesting in
that part are f_path-related things and Eric's descriptor-related
stuff). UFS regression fixes (it got broken last cycle). 9P fixes.
fs-cache series, DAX patches, Jan's file_remove_suid() work"
[ I'd say this is much more than "fixes and related cleanups". The
file_table locking rule change by Eric Dumazet is a rather big and
fundamental update even if the patch isn't huge. - Linus ]
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits)
9p: cope with bogus responses from server in p9_client_{read,write}
p9_client_write(): avoid double p9_free_req()
9p: forgetting to cancel request on interrupted zero-copy RPC
dax: bdev_direct_access() may sleep
block: Add support for DAX reads/writes to block devices
dax: Use copy_from_iter_nocache
dax: Add block size note to documentation
fs/file.c: __fget() and dup2() atomicity rules
fs/file.c: don't acquire files->file_lock in fd_install()
fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation
vfs: avoid creation of inode number 0 in get_next_ino
namei: make set_root_rcu() return void
make simple_positive() public
ufs: use dir_pages instead of ufs_dir_pages()
pagemap.h: move dir_pages() over there
remove the pointless include of lglock.h
fs: cleanup slight list_entry abuse
xfs: Correctly lock inode when removing suid and file capabilities
fs: Call security_ops->inode_killpriv on truncate
fs: Provide function telling whether file_remove_privs() will do anything
...
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: Yan, 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: Yan, Zheng <zyan@redhat.com>
In most cases that snap context is needed, we are holding
reference of CEPH_CAP_FILE_WR. So we can set ceph inode's
i_head_snapc when getting the CEPH_CAP_FILE_WR reference,
and make codes get snap context from i_head_snapc. This makes
the code simpler.
Another benefit of this change is that we can handle snap
notification more elegantly. Especially when snap context
is updated while someone else is doing write. The old queue
cap_snap code may set cap_snap's context to ether the old
context or the new snap context, depending on if i_head_snapc
is set. The new queue capp_snap code always set cap_snap's
context to the old snap context.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
file_remove_suid() is a misnomer since it removes also file capabilities
stored in xattrs and sets S_NOSEC flag. Also should_remove_suid() tells
something else than whether file_remove_suid() call is necessary which
leads to bugs.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
... returning -E... upon error and amount of data left in iter after
(possible) truncation upon success. Note, that normal case gives
a non-zero (positive) return value, so any tests for != 0 _must_ be
updated.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Conflicts:
fs/ext4/file.c
All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
There is no need to pass the total request length in the kiocb, as
we already get passed in through the iov_iter argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull more vfs updates from Al Viro:
"Assorted stuff from this cycle. The big ones here are multilayer
overlayfs from Miklos and beginning of sorting ->d_inode accesses out
from David"
* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (51 commits)
autofs4 copy_dev_ioctl(): keep the value of ->size we'd used for allocation
procfs: fix race between symlink removals and traversals
debugfs: leave freeing a symlink body until inode eviction
Documentation/filesystems/Locking: ->get_sb() is long gone
trylock_super(): replacement for grab_super_passive()
fanotify: Fix up scripted S_ISDIR/S_ISREG/S_ISLNK conversions
Cachefiles: Fix up scripted S_ISDIR/S_ISREG/S_ISLNK conversions
VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry)
SELinux: Use d_is_positive() rather than testing dentry->d_inode
Smack: Use d_is_positive() rather than testing dentry->d_inode
TOMOYO: Use d_is_dir() rather than d_inode and S_ISDIR()
Apparmor: Use d_is_positive/negative() rather than testing dentry->d_inode
Apparmor: mediated_filesystem() should use dentry->d_sb not inode->i_sb
VFS: Split DCACHE_FILE_TYPE into regular and special types
VFS: Add a fallthrough flag for marking virtual dentries
VFS: Add a whiteout dentry type
VFS: Introduce inode-getting helpers for layered/unioned fs environments
Infiniband: Fix potential NULL d_inode dereference
posix_acl: fix reference leaks in posix_acl_create
autofs4: Wrong format for printing dentry
...
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: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull Ceph changes from Sage Weil:
"On the RBD side, there is a conversion to blk-mq from Christoph,
several long-standing bug fixes from Ilya, and some cleanup from
Rickard Strandqvist.
On the CephFS side there is a long list of fixes from Zheng, including
improved session handling, a few IO path fixes, some dcache management
correctness fixes, and several blocking while !TASK_RUNNING fixes.
The core code gets a few cleanups and Chaitanya has added support for
TCP_NODELAY (which has been used on the server side for ages but we
somehow missed on the kernel client).
There is also an update to MAINTAINERS to fix up some email addresses
and reflect that Ilya and Zheng are doing most of the maintenance for
RBD and CephFS these days. Do not be surprised to see a pull request
come from one of them in the future if I am unavailable for some
reason"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (27 commits)
MAINTAINERS: update Ceph and RBD maintainers
libceph: kfree() in put_osd() shouldn't depend on authorizer
libceph: fix double __remove_osd() problem
rbd: convert to blk-mq
ceph: return error for traceless reply race
ceph: fix dentry leaks
ceph: re-send requests when MDS enters reconnecting stage
ceph: show nocephx_require_signatures and notcp_nodelay options
libceph: tcp_nodelay support
rbd: do not treat standalone as flatten
ceph: fix atomic_open snapdir
ceph: properly mark empty directory as complete
client: include kernel version in client metadata
ceph: provide seperate {inode,file}_operations for snapdir
ceph: fix request time stamp encoding
ceph: fix reading inline data when i_size > PAGE_SIZE
ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_close_sessions)
ceph: avoid block operation when !TASK_RUNNING (ceph_get_caps)
ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_sync)
rbd: fix error paths in rbd_dev_refresh()
...
when inode has inline data but its size > PAGE_SIZE (it was truncated
to larger size), previous direct read code return -EIO. This patch adds
code to return zeros for data whose offset > PAGE_SIZE.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
A bug is found in striped_read() of fs/ceph/file.c. striped_read() calls
ceph_zero_pape_vector_range(). The first argument, page_align + read + ret,
passed to ceph_zero_pape_vector_range() is wrong.
When a file has holes, this wrong parameter may cause memory corruption
either in kernal space or user space. Kernel space memory may be corrupted in
the case of non direct IO; user space memory may be corrupted in the case of
direct IO. In the latter case, the application doing direct IO may crash due
to memory corruption, as we have experienced.
The correct value should be initial_align + read + ret, where intial_align =
o_direct ? buf_align : io_align. Compared with page_align, the current page
offest, initial_align is the initial page offest, which should be used to
calculate the page and offset in ceph_zero_pape_vector_range().
Reported-by: caifeng zhu <zhucaifeng@unissoft-nj.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Now that we got rid of the bdi abuse on character devices we can always use
sb->s_bdi to get at the backing_dev_info for a file, except for the block
device special case. Export inode_to_bdi and replace uses of
mapping->backing_dev_info with it to prepare for the removal of
mapping->backing_dev_info.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull ceph updates from Sage Weil:
"The big item here is support for inline data for CephFS and for
message signatures from Zheng. There are also several bug fixes,
including interrupted flock request handling, 0-length xattrs, mksnap,
cached readdir results, and a message version compat field. Finally
there are several cleanups from Ilya, Dan, and Markus.
Note that there is another series coming soon that fixes some bugs in
the RBD 'lingering' requests, but it isn't quite ready yet"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (27 commits)
ceph: fix setting empty extended attribute
ceph: fix mksnap crash
ceph: do_sync is never initialized
libceph: fixup includes in pagelist.h
ceph: support inline data feature
ceph: flush inline version
ceph: convert inline data to normal data before data write
ceph: sync read inline data
ceph: fetch inline data when getting Fcr cap refs
ceph: use getattr request to fetch inline data
ceph: add inline data to pagecache
ceph: parse inline data in MClientReply and MClientCaps
libceph: specify position of extent operation
libceph: add CREATE osd operation support
libceph: add SETXATTR/CMPXATTR osd operations support
rbd: don't treat CEPH_OSD_OP_DELETE as extent op
ceph: remove unused stringification macros
libceph: require cephx message signature by default
ceph: introduce global empty snap context
ceph: message versioning fixes
...
Before any data write, convert inline data to normal data and set
i_inline_version to CEPH_INLINE_NONE. The OSD request that saves
inline data to object contains 3 operations (CMPXATTR, WRITE and
SETXATTR). It compares a xattr named 'inline_version' to prevent
old data overwrites newer data.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
we can't use getattr to fetch inline data while holding Fr cap,
because it can cause deadlock. If we need to sync read inline data,
drop cap refs first, then use getattr to fetch inline data.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
we can't use getattr to fetch inline data after getting Fcr caps,
because it can cause deadlock. The solution is try bringing inline
data to page cache when not holding any cap, and hope the inline
data page is still there after getting the Fcr caps. If the page
is still there, pin it in page cache for later IO.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
allow specifying position of extent operation in multi-operations
osd request. This is required for cephfs to convert inline data to
normal data (compare xattr, then write object).
Signed-off-by: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Ilya Dryomov <idryomov@redhat.com>
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: Yan, Zheng <zyan@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
Following sequence of events can happen.
- Client releases an inode, queues cap release message.
- A 'lookup' reply brings the same inode back, but the reply
doesn't contain xattrs because MDS didn't receive the cap release
message and thought client already has up-to-data xattrs.
The fix is force sending a getattr request to MDS if xattrs_version
is 0. The getattr mask is set to CEPH_STAT_CAP_XATTR, so MDS knows client
does not have xattr.
Signed-off-by: Yan, Zheng <zyan@redhat.com>
generic_write_checks() may update 'pos', so we need to pass 'pos'
to ceph_sync_write() and ceph_sync_direct_write();
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Yan, Zheng
Yanhu Cao
Luis Henriques
Linus Torvalds
Michal Hocko
Alexander Graf
Jeff Layton
Ilya Dryomov
Al Viro
Zhi Zhang
Nikolay Borisov
NeilBrown
Deepa Dinamani
Phil Turnbull
Christoph Hellwig
Kirill A. Shutemov
Geliang Tang
Dan Carpenter
Zhu, Caifeng
Jianpeng Ma
Jan Kara
David Howells
Yan, Zheng