svc_procfunc instances return __be32, not int
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
a) ERR_PTR(nfserr_something) is a bad idea;
IS_ERR() will be false for it.
b) mixing nfserr_.... with -EOPNOTSUPP is
even worse idea.
nfsd4_path() does both; caller expects to get NFS protocol error out it if
anything goes wrong, but if it does we either do not notice (see (a)) or get
host-endian negative (see (b)).
IOW, that's a case when we can't use ERR_PTR() to return error, even though we
return a pointer in case of success.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Coverity spotted a superfluous error check in nfs4_open_revalidate(). Remove
it.
Coverity: #cid 847
Test plan:
Code inspection; another pass through Coverity.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The "!inode" check in __nfs_revalidate_inode() occurs well after the first
time it is dereferenced, so get rid of it.
Coverity: #cid 1372, 1373
Test plan:
Code review; recheck with Coverity.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The original code confused a zero return code from pagevec_add() as success.
Test plan:
None.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If invalidate_inode_pages2() fails, then it should in principle just be
because the current process was signalled. In that case, we just want to
ensure that the inode's page cache remains marked as invalid.
Also add a helper to allow the O_DIRECT code to simply mark the page cache as
invalid once it is finished writing, instead of calling
invalidate_inode_pages2() itself.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The change in semantics for nfs_find_client() introduced by David breaks the
NFSv4 callback channel.
Also, replace another completely broken BUG_ON() in nfs_find_client(). In
initialised clients, clp->cl_cons_state == 0, and callers of that function
should in any case never want to see clients that are uninitialised.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
David forgot to do this. I'm not sure if this is the right place to put
it....
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If the RPC call tanked, we should not be checking the return value
of data->res.verf->committed, since it is unlikely to even be
initialised.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix two bugs:
- nfs_inode_remove_request will call nfs_clear_request, so we cannot
reference req->wb_page after it. Move the call to dec_zone_page_state so
that it occurs while req->wb_page is still valid.
- Calling nfs_clear_page_writeback is unnecessary since the radix tree
tags will have been cleared by the call to nfs_inode_remove_request.
Replace with a simple call to nfs_unlock_request.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Duh. addr.sin_port should be in network byte order.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make sure all dentries refs are released before calling kill_anon_super()
so that the assumption that generic_shutdown_super() can completely destroy
the dentry tree for there will be no external references holds true.
What was being done in the put_super() superblock op, is now done in the
kill_sb() filesystem op instead, prior to calling kill_anon_super().
The call to shrink_dcache_sb() is removed as it is redundant since
shrink_dcache_for_umount() will now be called after the cleanup routine.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Ian Kent <raven@themaw.net>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
GENERIC_ACL shouldn't be under Network File Systems (which made it depend
on NET) as far as I can tell. Having it there and having many (FS) config
symbols disabled gives this (which the patch fixes):
mm/built-in.o: In function `shmem_check_acl':
shmem_acl.c:(.text.shmem_check_acl+0x33): undefined reference to `posix_acl_permission'
fs/built-in.o: In function `generic_acl_get':
(.text.generic_acl_get+0x30): undefined reference to `posix_acl_to_xattr'
fs/built-in.o: In function `generic_acl_set':
(.text.generic_acl_set+0x75): undefined reference to `posix_acl_from_xattr'
fs/built-in.o: In function `generic_acl_set':
(.text.generic_acl_set+0x94): undefined reference to `posix_acl_valid'
fs/built-in.o: In function `generic_acl_set':
(.text.generic_acl_set+0xc1): undefined reference to `posix_acl_equiv_mode'
fs/built-in.o: In function `generic_acl_init':
(.text.generic_acl_init+0x7a): undefined reference to `posix_acl_clone'
fs/built-in.o: In function `generic_acl_init':
(.text.generic_acl_init+0xb4): undefined reference to `posix_acl_clone'
fs/built-in.o: In function `generic_acl_init':
(.text.generic_acl_init+0xc8): undefined reference to `posix_acl_create_masq'
fs/built-in.o: In function `generic_acl_chmod':
(.text.generic_acl_chmod+0x49): undefined reference to `posix_acl_clone'
fs/built-in.o: In function `generic_acl_chmod':
(.text.generic_acl_chmod+0x76): undefined reference to `posix_acl_chmod_masq'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Despite mm.h is not being exported header, it does contain one thing
which is part of userspace ABI -- value disabling OOM killer for given
process. So,
a) create and export include/linux/oom.h
b) move OOM_DISABLE define there.
c) turn bounding values of /proc/$PID/oom_adj into defines and export
them too.
Note: mass __KERNEL__ removal will be done later.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Separate out the concept of "queue congestion" from "backing-dev congestion".
Congestion is a backing-dev concept, not a queue concept.
The blk_* congestion functions are retained, as wrappers around the core
backing-dev congestion functions.
This proper layering is needed so that NFS can cleanly use the congestion
functions, and so that CONFIG_BLOCK=n actually links.
Cc: "Thomas Maier" <balagi@justmail.de>
Cc: "Jens Axboe" <jens.axboe@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: David Howells <dhowells@redhat.com>
Cc: Peter Osterlund <petero2@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the special_file() macro to check whether an inode is special instead of
open-coding it.
Acked-by: Mike Halcrow <mhalcrow@us.ibm.com>
Cc: Phillip Hellewell <phillip@hellewell.homeip.net>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
And the obsolete comment should be updated (or totally removed).
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Following function can drops d_count twice against one reference
by lookup_one_len.
<SOURCE>
/**
* sysfs_update_file - update the modified timestamp on an object attribute.
* @kobj: object we're acting for.
* @attr: attribute descriptor.
*/
int sysfs_update_file(struct kobject * kobj, const struct attribute * attr)
{
struct dentry * dir = kobj->dentry;
struct dentry * victim;
int res = -ENOENT;
mutex_lock(&dir->d_inode->i_mutex);
victim = lookup_one_len(attr->name, dir, strlen(attr->name));
if (!IS_ERR(victim)) {
/* make sure dentry is really there */
if (victim->d_inode &&
(victim->d_parent->d_inode == dir->d_inode)) {
victim->d_inode->i_mtime = CURRENT_TIME;
fsnotify_modify(victim);
/**
* Drop reference from initial sysfs_get_dentry().
*/
dput(victim);
res = 0;
} else
d_drop(victim);
/**
* Drop the reference acquired from sysfs_get_dentry() above.
*/
dput(victim);
}
mutex_unlock(&dir->d_inode->i_mutex);
return res;
}
</SOURCE>
PCI-hotplug (drivers/pci/hotplug/pci_hotplug_core.c) is only user of
this function. I confirmed that dentry of /sys/bus/pci/slots/XXX/*
have negative d_count value.
This patch removes unnecessary dput().
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Handle errors thrown in disk_sysfs_symlinks(), and propagate back to
caller.
The callers and associated functions don't do a real good job of handling
kobject errors anyway (add_partition, register_disk, rescan_partitions), so
this should do until something better comes along.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When IO error happens on metadata buffer, buffer is freed from memory and
later fsync() is called, filesystems like ext2 fail to report EIO. We
solve the problem by introducing a pointer to associated address space into
the buffer_head. When a buffer is removed from a list of metadata buffers
associated with an address space, IO error is transferred from the buffer to
the address space, so that fsync can later report it.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It is possible for the ->fopen callback from lockd into nfsd to find that an
answer cannot be given straight away (an upcall is needed) and so the request
has to be 'dropped', to be retried later. That error status is not currently
propagated back.
So:
Change nlm_fopen to return nlm error codes (rather than a private
protocol) and define a new nlm_drop_reply code.
Cause nlm_drop_reply to cause the rpc request to get rpc_drop_reply
when this error comes back.
Cause svc_process to drop a request which returns a status of
rpc_drop_reply.
[akpm@osdl.org: fix warning storm]
Cc: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When an nfs server shuts down, lockd needs to release all the locks even
though the client still holds them.
It should therefore not 'unmonitor' the clients, so that the files in nfs/sm
will still be there when the nfs server restarts, so that those clients will
be told to reclaim their locks.
However the hosts are fully unmonitored, so statd may well remove the files.
lockd has a test for 'sm_sticky' and avoid the unmonitor call if it is set,
but it is currently not set.
So set it when tearing down lockd.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Coverity noticed that the error handling code in the NFSv4 callback client
sets cb->cb_client to NULL, then calls rpc_shutdown_client with the NULL
pointer.
Coverity: #cid 1397
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We weren't actually checking for SHARE_ACCESS_WRITE, with the result that the
owner could open a non-writeable file for write!
Continue to allow DENY_WRITE only with write access.
Thanks to Jim Rees for reporting the bug.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If a client creates a file using an open which sets the mode to 000, or if a
chmod changes permissions after a file is opened, then situations may arise
where an NFS client knows that some IO is permitted (because a process holds
the file open), but the NFS server does not (because it doesn't know about the
open, and only sees that the IO conflicts with the current mode of the file).
As a hack to solve this problem, NFS servers normally allow the owner to
override permissions on IO. The client can still enforce correct
permissions-checking on open by performing an explicit access check.
In NFSv4 the client can rely on the explicit on-the-wire open instead of an
access check.
Therefore we should not be allowing the owner to override permissions on an
over-the-wire open!
However, we should still allow the owner to override permissions in the case
where the client is claiming an open that it already made either before a
reboot, or while it was holding a delegation.
Thanks to Jim Rees for reporting the bug.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There's no locking for ->d_revalidate, so fuse_dentry_revalidate() should use
dget_parent() instead of simply dereferencing ->d_parent.
Due to topology changes in the directory tree the parent could become negative
or be destroyed while being used. There hasn't been any reports about this
yet.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fuse considered it an error (EIO) if lookup returned a directory inode, to
which a dentry already refered. This is because directory aliases are not
allowed.
But in a network filesystem this could happen legitimately, if a directory is
moved on a remote client. This patch attempts to relax the restriction by
trying to first evict the offending alias from the cache. If this fails, it
still returns an error (EBUSY).
A rarer situation is if an mkdir races with an indenpendent lookup, which
finds the newly created directory already moved. In this situation the mkdir
should return success, but that would be incorrect, since the dentry cannot be
instantiated, so return EBUSY.
Previously checking for a directory alias and instantiation of the dentry
weren't done atomically in lookup/mkdir, hence two such calls racing with each
other could create aliased directories. To prevent this introduce a new
per-connection mutex: fuse_conn->inst_mutex, which is taken for instantiations
with a directory inode.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix a spurious BUG in an unlikely race, where at least three parallel lookups
return the same inode, but with different file type. This has not yet been
observed in real life.
Allowing unlimited retries could delay fuse_iget() indefinitely, but this is
really for the broken userspace filesystem to worry about.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
An inode could be returned by independent parallel lookups, in this case an
update of the lookup counter could be lost resulting in a memory leak in
userspace.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fuse didn't always call i_size_write() with i_mutex held which caused rare
hangs on SMP/32bit. This bug has been present since fuse-2.2, well before
being merged into mainline.
The simplest solution is to protect i_size_write() with the per-connection
spinlock. Using i_mutex for this purpose would require some restructuring of
the code and I'm not even sure it's always safe to acquire i_mutex in all
places i_size needs to be set.
Since most of vmtruncate is already duplicated for other reasons, duplicate
the remaining part as well, making all i_size_write() calls internal to fuse.
Using i_size_write() was unnecessary in fuse_init_inode(), since this function
is only called on a newly created locked inode.
Reported by a few people over the years, but special thanks to Dana Henriksen
who was persistent enough in helping me debug it.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Actually, the decimal representation of a 32-bit signed number can take 12
bytes, including the \0.
And then some code adds a \n as well, so let's give it 13 bytes.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is Eric Sesterhenn's jbd patch applied to jbd2.
Commit: 41716c7c21
His words:
Since commit d1807793e1 we dereference a NULL
pointer. Coverity id #1432. We set journal to NULL, and use it directly
afterwards.
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It is silly to use non-static variable for writting zeroes to the file.
And more seriously, foffset in core dump file dump function was incremented
too much, so some parts of core dump were shifted by size of few phdrs and
notes down, so although gdb was able to load that file, it did not make lot
of sense - in my test case data pages were shifted down by about 900 bytes.
Signed-off-by: Petr Vandrovec <petr@vandrovec.name>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* missing cpu_to_le64() for ChangeTime (introduced by
[CIFS] Legacy time handling for Win9x and OS/2 part 1)
* missing le16_to_cpu() for DialectIndex (introduced by
[CIFS] Do not send newer QFSInfo to legacy servers which can not support it)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
[GFS2] Update git tree name/location
[DLM] fix iovec length in recvmsg
[GFS2] Pass the correct value to kunmap_atomic
[GFS2] Fix bug where lock not held
[DLM] Kconfig: don't show an empty DLM menu
[GFS2] Fix uninitialised variable
[GFS2] Fix a size calculation error
The file based core dump code was broken by pipe changes - a relative
llseek returns the absolute file position on success, not the relative
one, so dump_seek() always failed when invoked with non-zero current
position.
Only success/failure can be tested with relative lseek, we have to trust
kernel that on success we've got right file offset. With this fix in
place I have finally real core files instead of 1KB fragments...
Signed-off-by: Petr Vandrovec <petr@vandrovec.name>
[ Cleaned it up a bit while here - use SEEK_CUR instead of hardcoding 1 ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: (27 commits)
[CIFS] Missing flags2 for DFS
[CIFS] Workaround incomplete byte length returned by some
[CIFS] cifs Kconfig: don't select CONNECTOR
[CIFS] Level 1 QPathInfo needed for proper OS2 support
[CIFS] fix typo in previous patch
[CIFS] Fix old DOS time conversion to handle timezone
[CIFS] Do not need to adjust for Jan/Feb for leap day
[CIFS] Fix leaps year calculation for years after 2100
[CIFS] readdir (ffirst) enablement of accurate timestamps from legacy servers
[CIFS] Fix compiler warning with previous patch
[CIFS] Fix typo
[CIFS] Allow for 15 minute TZs (e.g. Nepal) and be more explicit about
[CIFS] Fix readdir of large directories for backlevel servers
[CIFS] Allow LANMAN21 support even in both POSIX non-POSIX path
[CIFS] Make use of newer QFSInfo dependent on capability bit instead of
[CIFS] Do not send newer QFSInfo to legacy servers which can not support it
[CIFS] Fix typo in name of new cifs_show_stats
[CIFS] Rename server time zone field
[CIFS] Handle legacy servers which return undefined time zone
[CIFS] CIFS support for /proc/<pid>/mountstats part 1
...
Manual conflict resolution in fs/cifs/connect.c
The DLM always passes the iovec length as 1, this is wrong when the circular
buffer wraps round.
Signed-Off-By: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Pass kaddr rather than (incorrect) struct page to kunmap_atomic.
Signed-off-by: Russell Cattelan <cattelan@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
The log lock needs to be held when manipulating the counter
for the number of free journal blocks.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Don't show an empty "Distributed Lock Manager" menu if IP_SCTP=n.
Reported by Dmytro Bagrii in kernel Bugzilla #7268.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David Teigland <teigland@redhat.com>
Signed-off-by: Patrick Caulfield <pcaulfie@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This fixes a bug where, in certain cases an uninitialised variable
could cause a dereference of a NULL pointer in gfs2_commit_write().
Also a typo in a comment is fixed at the same time.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Fix a size calculation error.
The size was incorrect being computed as a
negative length and then being passed to an
unsigned parameter.
This in turn would cause the allocator to
think it needed enough meta data to store
a gigabyte file for every file created.
Signed-off-by: Russell Cattelan <cattelan@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
`select' is a bit obnoxious: the option keeps on coming back
and it's hard to work out what to do to make it go away again.
The use of `depends on' is preferred (although it has
usability problems too..)
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Currently ioprio_best function first checks wethere aioprio or bioprio equals
IOPRIO_CLASS_NONE (ioprio_valid() macros does that) and if it is so it returns
bioprio/aioprio appropriately. Thus the next four lines, that set aclass/bclass
to IOPRIO_CLASS_BE, if aclass/bclass == IOPRIO_CLASS_NONE, are never executed.
The second problem: if aioprio from class IOPRIO_CLASS_NONE and bioprio from
class IOPRIO_CLASS_IDLE are passed to ioprio_best function, it will return
IOPRIO_CLASS_IDLE. It means that during __make_request we can merge two
requests and set the priority of merged request to IDLE, while one of
the initial requests originates from a process with NONE (default) priority.
So we can get a situation when a process with default ioprio will experience
IO starvation, while there is no process from real-time class in the system.
Just removing ioprio_valid check should correct situation.
Signed-off-by: Vasily Tarasov <vtaras@openvz.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Al Viro