Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

While we always want to align to the next page and/or the beginning of
the tail buffer when we call xdr_set_next_page(), the functions
xdr_align_data() and xdr_expand_hole() really want to align to the next
object in that next page or tail.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

rpc_prepare_reply_pages() currently expects the 'hdrsize' argument to
contain the length of the data that we expect to want placed in the head
kvec plus a count of 1 word of padding that is placed after the page data.
This is very confusing when trying to read the code, and sometimes leads
to callers adding an arbitrary value of '1' just in order to satisfy the
requirement (whether or not the page data actually needs such padding).

This patch aims to clarify the code by changing the 'hdrsize' argument
to remove that 1 word of padding. This means we need to subtract the
padding from all the existing callers.

Fixes: 02ef04e4 ("NFS: Account for XDR pad of buf->pages")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Fix up xdr_read_pages() so that it can handle object lengths that are
larger than the page length, by simply aligning to the next object in
the buffer tail.
The function will continue to return the length of the truncate object
data that actually fit into the pages.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Allow xdr_set_iov() to set a base so that we can use it to set the
cursor to a specific position in the kvec buffer.

If the new base overflows the kvec/pages buffer in either xdr_set_iov()
or xdr_set_page_base(), then truncate it so that we point to the end of
the buffer.

Finally, change both function to return the number of bytes remaining to
read in their buffers.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We already know that the head buffer and page are empty, so if there is
any data, it is in the tail.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We can fit the device_addr4 opaque data padding in the pages.

Fixes: cf500bac ("SUNRPC: Introduce rpc_prepare_reply_pages()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Use the existing xdr_stream_decode_string_dup() to safely decode into
kmalloced strings.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Ensure that we report the correct netid when using UDP or RDMA
transports to the DSes.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We want to enable RDMA and UDP as valid transport methods if a
GETDEVICEINFO call specifies it. Do so by adding a parser for the
netid that translates it to an appropriate argument for the RPC
transport layer.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If the pNFS metadata server advertises multiple addresses for the same
data server, we should try to connect to just one protocol family and
transport type on the assumption that homogeneity will improve performance.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Switch the mount code to use xprt_find_transport_ident() and to check
the results before allowing the mount to proceed.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

After we've looked up the transport module, we need to ensure it can't
go away until we've finished running the transport setup code.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

According to RFC5666, the correct netid for an IPv6 addressed RDMA
transport is "rdma6", which we've supported as a mount option since
Linux-4.7. The problem is when we try to load the module "xprtrdma6",
that will fail, since there is no modulealias of that name.

Fixes: 181342c5 ("xprtrdma: Add rdma6 option to support NFS/RDMA IPv6")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

If the directory is changing, causing the page cache to get invalidated
while we are listing the contents, then the NFS client is currently forced
to read in the entire directory contents from scratch, because it needs
to perform a linear search for the readdir cookie. While this is not
an issue for small directories, it does not scale to directories with
millions of entries.
In order to be able to deal with large directories that are changing,
add a heuristic to ensure that if the page cache is empty, and we are
searching for a cookie that is not the zero cookie, we just default to
performing uncached readdir.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

If we're doing uncached readdir, allocate multiple pages in order to
try to avoid duplicate RPC calls for the same getdents() call.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

If the server is handing out monotonically increasing readdir cookie values,
then we can optimise away searches through pages that contain cookies that
lie outside our search range.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

If the server insists on using the readdir verifiers in order to allow
cookies to expire, then we should ensure that we cache the verifier
with the cookie, so that we can return an error if the application
tries to use the expired cookie.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

If the server returns NFS4ERR_NOT_SAME or tells us that the cookie is
bad in response to a READDIR call, then we should empty the page cache
so that we can fill it from scratch again.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

If we're ever going to allow support for servers that use the readdir
verifier, then that use needs to be managed by the middle layers as
those need to be able to reject cookies from other verifiers.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

The descriptor and the struct nfs_entry are both large structures,
so don't allocate them from the stack.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

Clean up nfs_do_filldir().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

Remove the redundant caching of the credential in struct
nfs_open_dir_context.
Pass the buffer size as an argument to nfs_readdir_xdr_filler().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

Support readdir buffers of up to 1MB in size so that we can read
large directories using few RPC calls.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

We don't need to store a hash, so replace struct qstr with a simple
const char pointer and length.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

The kmapped pointer is only used once per loop to check if we need to
exit.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

If a readdir call returns more data than we can fit into one page
cache page, then allocate a new one for that data rather than
discarding the data.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

Refactor to use pagecache_get_page() so that we can fill the page
in multiple stages.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

Clean up handling of the case where there are no entries in the readdir
reply.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

Since the 'eof_index' is only ever used as a flag, make it so.
Also add a flag to detect if the page has been completely filled.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

Ensure that the contents of struct nfs_open_dir_context are consistent
by setting them under the file->f_lock from a private copy (that is
known to be consistent).
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Dave Wysochanski <dwysocha@redhat.com>

Currently, the client will always ask for security_labels if the server
returns that it supports that feature regardless of any LSM modules
(such as Selinux) enforcing security policy. This adds performance
penalty to the READDIR operation.

Client adjusts superblock's support of the security_label based on
the server's support but also current client's configuration of the
LSM modules. Thus, prior to using the default bitmask in READDIR,
this patch checks the server's capabilities and then instructs
READDIR to remove FATTR4_WORD2_SECURITY_LABEL from the bitmask.

v5: fixing silly mistakes of the rushed v4
v4: simplifying logic
v3: changing label's initialization per Ondrej's comment
v2: dropping selinux hook and using the sb cap.
Suggested-by: Ondrej Mosnacek <omosnace@redhat.com>
Suggested-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Fixes: 2b0143b5 ("VFS: normal filesystems (and lustre): d_inode() annotations")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Currently, we wake up the tasks by priority queue ordering, which means
that we ignore the batching that is supposed to help with QoS issues.

Fixes: c049f8ea ("SUNRPC: Remove the bh-safe lock requirement on the rpc_wait_queue->lock")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

We need to respect the NFS_MOUNT_SOFTREVAL flag in _nfs4_proc_lookupp,
by timing out if the server is unavailable.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>