ClearPageUptodate() will just cause races here. What we really want to do
is to invalidate the page cache.
Signed-off-by: Trond Myklebust <[email protected]>
Fix wraparound issue with nfsi->cache_change_attribute. If it is found
to lie in the future, then update it to lie in the past. Patch based on
a suggestion by Neil Brown.
..and minor micro-optimisation: avoid reading 'jiffies' more than once in
nfs_update_inode().
Signed-off-by: Trond Myklebust <[email protected]>
Currently only root can trigger a referral automount because only root
can access rpc_pipefs directories. Enabling read access to non-root
should be harmless (they can still not access the pipes themselves)
and will suffice to fix this problem.
Signed-off-by: Trond Myklebust <[email protected]>
nfs_lookup_revalidate and friends are not serialised, so it is currently
quite possible for the dentry to be revalidated, and then have the
updated verifier replaced with an older value by another process.
Signed-off-by: Trond Myklebust <[email protected]>
If the fileid of the cached dentry fails to match that returned by
the readdir call, then we should also d_drop. Try to take into account the
fact that on NFSv4, readdir may return the "mounted_on_fileid" by looking
for submounts.
Signed-off-by: Trond Myklebust <[email protected]>
Make sure that nfs_readdir_lookup() handles negative dentries correctly.
If d_lookup() returns a negative dentry, then we need to d_drop() that
since readdir shows that it should be positive.
Signed-off-by: Trond Myklebust <[email protected]>
When a file is being scheduled for deletion by means of the sillyrename
mechanism, it makes sense to start out writeback of the dirty data as
soon as possible in order to ensure that the delete can occur. Examples of
cases where this is an issue include "rm -rf", which will busy-wait until
the file is closed, and the sillyrename completes.
Signed-off-by: Trond Myklebust <[email protected]>
The filehandle that is passed into nfs4_create_referral_server is
not initialised. The expectation is that nfs4_create_referral_server will
initialise it, and return it to the caller.
Signed-off-by: Trond Myklebust <[email protected]>
The error values are already propagated through task->tk_status, and
none of the callers check one without checking the other, so we can
drop the return value.
Signed-off-by: Trond Myklebust <[email protected]>
rpc_call_async() will always call rpc_release_calldata(), so it is an
error for __nlm_async_call() to do so as well.
Signed-off-by: Trond Myklebust <[email protected]>
Prevent the call to invalidate_inode_pages2() from racing with file writes
by taking the inode->i_mutex across the page cache flush and invalidate.
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
NFS: Fix race in nfs_release_page()
invalidate_inode_pages2() may find the dirty bit has been set on a page
owing to the fact that the page may still be mapped after it was locked.
Only after the call to unmap_mapping_range() are we sure that the page
can no longer be dirtied.
In order to fix this, NFS has hooked the releasepage() method and tries
to write the page out between the call to unmap_mapping_range() and the
call to remove_mapping(). This, however leads to deadlocks in the page
reclaim code, where the page may be locked without holding a reference
to the inode or dentry.
Fix is to add a new address_space_operation, launder_page(), which will
attempt to write out a dirty page without releasing the page lock.
Signed-off-by: Trond Myklebust <[email protected]>
Also, the bare SetPageDirty() can skew all sort of accounting leading to
other nasties.
[[email protected]: cleanup]
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Trond Myklebust <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
We're really accounting for the same page twice now: once in
generic_writepages(), and once in nfs_scan_dirty().
Signed-off-by: Trond Myklebust <[email protected]>
There is now no reason to account for the dirty pages in the NFS code,
since the VM code will now do it for us via __set_page_dirty_nobuffers(),
and set_page_writeback().
We still need to keep the accounting of stable writes, though.
Signed-off-by: Trond Myklebust <[email protected]>
This will ensure that we can call set_page_writeback() from within
nfs_writepage(), which is always called with the page lock set.
Signed-off-by: Trond Myklebust <[email protected]>
We will want to allow nfs_writepage() to distinguish between pages that
have been marked as dirty by the VM, and those that have been marked as
dirty by nfs_updatepage().
In the former case, the entire page will want to be written out, and so any
requests that were pending need to be flushed out first.
Signed-off-by: Trond Myklebust <[email protected]>
Maintaining two parallel ways of doing synchronous writes is rather
pointless. This patch gets rid of the legacy nfs_writepage_sync(), and
replaces it with the faster asynchronous writes.
Signed-off-by: Trond Myklebust <[email protected]>
We always ensure that the nfs_open_context holds a reference to the dentry,
so the test in nfs_writepage() for whether or not the inode is referenced
is redundant.
Signed-off-by: Trond Myklebust <[email protected]>
This will allow fast lookup of the nfs_page from the struct page instead of
having to search the radix tree.
Signed-off-by: Trond Myklebust <[email protected]>
All internal RPC client operations should no longer depend on the BKL,
however lockd and NFS callbacks may still require it.
Signed-off-by: Trond Myklebust <[email protected]>
Currently nfs_sync_inode_wait() will fail to loop correctly when we call
nfs_sync_inode_wait with the FLUSH_INVALIDATE argument.
Signed-off-by: Trond Myklebust <[email protected]>
We must always call ->read_done() before we truncate the page data, or
decide to flag an error. The reasons are that
in NFSv2, ->read_done() is where the eof flag gets set.
in NFSv3/v4 ->read_done() handles EJUKEBOX-type errors, and
v4 state recovery.
However, we need to mark the pages as uptodate before we deal with short
read errors, since we may need to modify the nfs_read_data arguments.
We therefore split the current nfs_readpage_result() into two parts:
nfs_readpage_result(), which calls ->read_done() etc, and
nfs_readpage_retry(), which subsequently handles short reads.
Note: Removing the code that retries in case of a short read also fixes a
bug in nfs_direct_read_result(), which used to return a corrupted number of
bytes.
Signed-off-by: Trond Myklebust <[email protected]>
Use RCU to ensure that we can safely call rpc_finish_wakeup after we've
called __rpc_do_wake_up_task. If not, there is a theoretical race, in which
the rpc_task finishes executing, and gets freed first.
Signed-off-by: Trond Myklebust <[email protected]>
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 <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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 <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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 <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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 <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
If try_to_release_page() is called with a zero gfp mask, then the
filesystem is effectively denied the possibility of sleeping while
attempting to release the page. There doesn't appear to be any valid
reason why this should be banned, given that we're not calling this from a
memory allocation context.
For this reason, change the gfp_mask argument of the call to GFP_KERNEL.
Signed-off-by: Trond Myklebust <[email protected]>
Cc: Steve Dickson <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Commit ca4aa09635 fixed waiting for the
structure to get initialised, but it is also possible to break out of
the loop while still in TASK_INTERRUPTIBLE.
Replace the whole thing by wait_event_interruptible, which is much more
readable, and doesn't suffer from these problems.
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
NFS_CS_INITING > NFS_CS_READY, so instead of waiting for the structure to
get initialised, we currently immediately jump out of the loop without ever
sleeping.
Signed-off-by: Trond Myklebust <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
RFC3530 states that the registered port 2049 for the NFS protocol should be
the default configuration in order to allow clients not to use the RPC
binding protocols.
If the mount program sends us a port=0, we therefore substitute port=2049.
Signed-off-by: Trond Myklebust <[email protected]>
Retry a few times before we give up: the error is usually due to ordering
issues with asynchronous RPC calls.
Signed-off-by: Trond Myklebust <[email protected]>
Currently, a read() request will return EIO even if the file has been
deleted on the server, simply because that is what the VM will return
if the call to readpage() fails to update the page.
Ensure that readpage() marks the inode as stale if it receives an ESTALE.
Then return that error to userland.
Signed-off-by: Trond Myklebust <[email protected]>
If the open intents tell us that a given lookup is going to result in a,
exclusive create, we currently optimize away the lookup call itself. The
reason is that the lookup would not be atomic with the create RPC call, so
why do it in the first place?
A problem occurs, however, if the VFS aborts the exclusive create operation
after the lookup, but before the call to create the file/directory: in this
case we will end up with a hashed negative dentry in the dcache that has
never been looked up.
Fix this by only actually hashing the dentry once the create operation has
been successfully completed.
Signed-off-by: Trond Myklebust <[email protected]>
There is no guarantee that the parent task still exists when we exit from
the portmapper. Save the xprt instead.
Signed-off-by: Trond Myklebust <[email protected]>
In a subsequent patch, this will allow the portmapper to take a reference
to the rpc_xprt for which it is updating the port number, fixing an Oops.
Signed-off-by: Trond Myklebust <[email protected]>
- Ensure that the task aborts the RPC call only when it has actually timed out.
- Ensure that req->rq_majortimeo is initialised correctly.
Signed-off-by: Trond Myklebust <[email protected]>
In case of any of the above errors occuring, delay for 3 seconds, then
handle as if it were a timeout error.
Signed-off-by: Trond Myklebust <[email protected]>
A pinned inode may in theory end up filling memory with cached ACCESS
calls. This patch ensures that the VM may shrink away the cache in these
particular cases.
The shrinker works by iterating through the list of inodes on the global
nfs_access_lru_list, and removing the least recently used access
cache entry until it is done (or until the entire cache is empty).
Signed-off-by: Trond Myklebust <[email protected]>
The current access cache only allows one entry at a time to be cached for each
inode. Add a per-inode red-black tree in order to allow more than one to
be cached at a time.
Should significantly cut down the time spent in path traversal for shared
directories such as ${PATH}, /usr/share, etc.
Signed-off-by: Trond Myklebust <[email protected]>
The logic in nfs_direct_read_schedule and nfs_direct_write_schedule can
allow data->npages to be one larger than rpages. This causes a page
pointer to be written beyond the end of the pagevec in nfs_read_data (or
nfs_write_data).
Fix this by making nfs_(read|write)_alloc() calculate the size of the
pagevec array, and initialise data->npages.
Also get rid of the redundant argument to nfs_commit_alloc().
Signed-off-by: Trond Myklebust <[email protected]>
Cc: Chuck Lever <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
The check in open_exec() for inode->i_mode & 0111 has been made
redundant by the fix to permission().
Signed-off-by: Trond Myklebust <[email protected]>
(cherry picked from 1d3741c5d991686699f100b65b9956f7ee7ae0ae commit)
The check in prepare_binfmt() for inode->i_mode & 0111 is redundant,
since open_exec() will already have done that.
Signed-off-by: Trond Myklebust <[email protected]>
(cherry picked from 822dec482ced07af32c378cd936d77345786572b commit)
Currently, the access() call will return incorrect information on NFS if
there exists an ACL that grants execute access to the user on a regular
file. The reason the information is incorrect is that the VFS overrides
this execute access in open_exec() by checking (inode->i_mode & 0111).
This patch propagates the VFS execute bit check back into the generic
permission() call.
Signed-off-by: Trond Myklebust <[email protected]>
(cherry picked from 64cbae98848c4c99851cb0a405f0b4982cd76c1e commit)
This is needed in order to handle any NFS4ERR_DELAY errors that might be
returned by the server. It also ensures that we map the NFSv4 errors before
they are returned to userland.
Signed-off-by: Trond Myklebust <[email protected]>
(cherry picked from 71c12b3f0abc7501f6ed231a6d17bc9c05a238dc commit)