Currently MAY_ACCESS means that filesystems must check the permissions
right then and not rely on cached results or the results of future
operations on the object. This can be because of a call to sys_access() or
because of a call to chdir() which needs to check search without relying on
any future operations inside that dir. I plan to use MAY_ACCESS for other
purposes in the security system, so I split the MAY_ACCESS and the
MAY_CHDIR cases.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
nfs_commit_inode() needs to be defined irrespectively of whether or not
we are supporting NFSv3 and NFSv4.
Allow the compiler to optimise away code in the NFSv2-only case by
converting it into an inlined stub function.
Reported-and-tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
See https://bugzilla.kernel.org/show_bug.cgi?id=16056
If other processes are blocked waiting for kswapd to free up some memory so
that they can make progress, then we cannot allow kswapd to block on those
processes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
In root_nfs_name() it does the following:
if (strlen(buf) + strlen(cp) > NFS_MAXPATHLEN) {
printk(KERN_ERR "Root-NFS: Pathname for remote directory too long.\n");
return -1;
}
sprintf(nfs_export_path, buf, cp);
In the original code if (strlen(buf) + strlen(cp) == NFS_MAXPATHLEN)
then the sprintf() would lead to an overflow. Generally the rest of the
code assumes that the path can have NFS_MAXPATHLEN (1024) characters and
a NUL terminator so the fix is to add space to the nfs_export_path[]
buffer.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The current shrinker implementation requires the registered callback
to have global state to work from. This makes it difficult to shrink
caches that are not global (e.g. per-filesystem caches). Pass the shrinker
structure to the callback so that users can embed the shrinker structure
in the context the shrinker needs to operate on and get back to it in the
callback via container_of().
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Apparently, we have never been able to set the atime correctly from the
NFSv4 client.
Reported-by: 小倉一夫 <ka-ogura@bd6.so-net.ne.jp>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Currently, we do not display the minor version mount parameter in the
/proc mount info.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Put the code that is common to both the referral and ordinary mount cases
into a common helper routine.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
S_ISDIR(fsinfo.fattr->mode) checks the file type rather than the mode bits,
so we should be checking for the NFS_ATTR_FATTR_TYPE fattr property.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
J.R. Okajima reports that the call to sync_inode() in nfs_wb_page() can
deadlock with other writeback flush calls. It boils down to the fact
that we cannot ever call writeback_single_inode() while holding a page
lock (even if we do set nr_to_write to zero) since another process may
already be waiting in the call to do_writepages(), and so will deny us
the I_SYNC lock.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If we exit from nfs_commit_inode() without ensuring that the COMMIT rpc
call has been completed, we must re-mark the inode as dirty. Otherwise,
future calls to sync_inode() with the WB_SYNC_ALL flag set will fail to
ensure that the data is on the disk.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Commit 9c7e7e2337 (NFS: Don't call iput() in
nfs_access_cache_shrinker) unintentionally removed the spin unlock for the
inode->i_lock.
Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
- C99 knows about USHRT_MAX/SHRT_MAX/SHRT_MIN, not
USHORT_MAX/SHORT_MAX/SHORT_MIN.
- Make SHRT_MIN of type s16, not int, for consistency.
[akpm@linux-foundation.org: fix drivers/dma/timb_dma.c]
[akpm@linux-foundation.org: fix security/keys/keyring.c]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
iput() can potentially attempt to allocate memory, so we should avoid
calling it in a memory shrinker. Instead, rely on the fact that iput() will
call nfs_access_zap_cache().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Both iput() and put_rpccred() might allocate memory under certain
circumstances, so make sure that we don't recurse and deadlock...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We do not want to have the state recovery thread kick off and wait for a
memory reclaim, since that may deadlock when the writebacks end up
waiting for the state recovery thread to complete.
The safe thing is therefore to use GFP_NOFS in all open, close,
delegation return, lock, etc. operations that may be called by the
state recovery thread.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I'm about to change task->tk_start from a jiffies value to a ktime_t
value in order to make RPC RTT reporting more precise.
Recently (commit dc96aef9) nfs4_renew_done() started to reference
task->tk_start so that a jiffies value no longer had to be passed
from nfs4_proc_async_renew(). This allowed the calldata to point to
an nfs_client instead.
Changing task->tk_start to a ktime_t value makes it effectively
useless for renew timestamps, so we need to restore the pre-dc96aef9
logic that provided a jiffies "start" timestamp to nfs4_renew_done().
Both an nfs_client pointer and a timestamp need to be passed to
nfs4_renew_done(), so create a new nfs_renewdata structure that
contains both, resembling what is already done for delegreturn,
lock, and unlock.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up:
fs/nfs/iostat.h: In function ‘nfs_add_server_stats’:
fs/nfs/iostat.h:41: warning: comparison between signed and unsigned integer expressions
fs/nfs/iostat.h:41: warning: comparison between signed and unsigned integer expressions
fs/nfs/iostat.h:41: warning: comparison between signed and unsigned integer expressions
fs/nfs/iostat.h:41: warning: comparison between signed and unsigned integer expressions
Commit fce22848 replaced the open-coded per-cpu logic in several
functions in fs/nfs/iostat.h with a single invocation of
this_cpu_ptr(). This macro assumes its second argument is signed,
not unsigned.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: fscache_uniq takes a string, so it should be included
with the other string mount option definitions, by convention.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Seen with -Wextra:
/home/cel/linux/fs/nfs/fscache.c: In function ‘__nfs_readpages_from_fscache’:
/home/cel/linux/fs/nfs/fscache.c:479: warning: comparison between signed and unsigned integer expressions
The comparison implicitly converts "int" to "unsigned", making it
safe. But there's no need for the implicit type conversions here, and
the dfprintk() already uses a "%u" formatter for "npages." Better to
reduce confusion.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the server has given us a delegation on a file, we _know_ that we can
cache the attribute information even when the user has specified 'noac'.
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Keep a global count of how many referrals that the current task has
traversed on a path lookup. Return ELOOP if the count exceeds
MAX_NESTED_LINKS.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Move the O_EXCL open handling into _nfs4_do_open() where it belongs. Doing
so also allows us to reuse the struct fattr from the opendata.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>