NFS: More readdir cleanups

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 Mykle

NFS: More readdir cleanups

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>

show more ...

NFS: Support larger readdir buffers

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@hammerspa

NFS: Support larger readdir buffers

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>

show more ...

NFS: Simplify struct nfs_cache_array_entry

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@hammers

NFS: Simplify struct nfs_cache_array_entry

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>

show more ...

NFS: Replace kmap() with kmap_atomic() in nfs_readdir_search_array()

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

NFS: Replace kmap() with kmap_atomic() in nfs_readdir_search_array()

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>

show more ...

NFS: Remove unnecessary kmap in nfs_readdir_xdr_to_array()

The kmapped pointer is only used once per loop to check if we need to
exit.

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

NFS: Remove unnecessary kmap in nfs_readdir_xdr_to_array()

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>

show more ...

NFS: Don't discard readdir results

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

NFS: Don't discard readdir results

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>

show more ...

NFS: Clean up directory array handling

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>
Reviewe

NFS: Clean up directory array handling

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>

show more ...

NFS: Clean up nfs_readdir_page_filler()

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:

NFS: Clean up nfs_readdir_page_filler()

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>

show more ...

NFS: Clean up readdir struct nfs_cache_array

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 My

NFS: Clean up readdir struct nfs_cache_array

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>

show more ...

NFS: Ensure contents of struct nfs_open_dir_context are consistent

Ensure that the contents of struct nfs_open_dir_context are consistent
by setting them under the file->f_lock from a private copy (

NFS: Ensure contents of struct nfs_open_dir_context are consistent

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>

show more ...

SUNRPC: Add xdr_set_scratch_page() and xdr_reset_scratch_buffer()

Clean up: De-duplicate some frequently-used code.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

NFS: Don't gratuitously clear the inode cache when lookup failed

[ Upstream commit 47397915ede0192235474b145ebcd81b37b03624 ]

The fact that the lookup revalidation failed, does not mean that the
in

NFS: Don't gratuitously clear the inode cache when lookup failed

[ Upstream commit 47397915ede0192235474b145ebcd81b37b03624 ]

The fact that the lookup revalidation failed, does not mean that the
inode contents have changed.

Fixes: 5ceb9d7fdaaf ("NFS: Refactor nfs_lookup_revalidate()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

NFS: Don't revalidate the directory permissions on a lookup failure

[ Upstream commit 82e7ca1334ab16e2e04fafded1cab9dfcdc11b40 ]

There should be no reason to expect the directory permissions to cha

NFS: Don't revalidate the directory permissions on a lookup failure

[ Upstream commit 82e7ca1334ab16e2e04fafded1cab9dfcdc11b40 ]

There should be no reason to expect the directory permissions to change
just because the directory contents changed or a negative lookup timed
out. So let's avoid doing a full call to nfs_mark_for_revalidate() in
that case.
Furthermore, if this is a negative dentry, and we haven't actually done
a new lookup, then we have no reason yet to believe the directory has
changed at all. So let's remove the gratuitous directory inode
invalidation altogether when called from
nfs_lookup_revalidate_negative().

Reported-by: Geert Jansen <gerardu@amazon.com>
Fixes: 5ceb9d7fdaaf ("NFS: Refactor nfs_lookup_revalidate()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

NFS: Remove unnecessary inode lock in nfs_fsync_dir()

nfs_inc_stats() is already thread-safe, and there are no other reasons
to hold the inode lock here.

Signed-off-by: Trond Myklebust <trond.mykle

NFS: Remove unnecessary inode lock in nfs_fsync_dir()

nfs_inc_stats() is already thread-safe, and there are no other reasons
to hold the inode lock here.

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

show more ...

NFS: Remove unnecessary inode locking in nfs_llseek_dir()

Remove the contentious inode lock, and instead provide thread safety
using the file->f_lock spinlock.

Signed-off-by: Trond Myklebust <trond

NFS: Remove unnecessary inode locking in nfs_llseek_dir()

Remove the contentious inode lock, and instead provide thread safety
using the file->f_lock spinlock.

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

show more ...

nfs: Fix security label length not being reset

nfs_readdir_page_filler() iterates over entries in a directory, reusing
the same security label buffer, but does not reset the buffer's length.
This ca

nfs: Fix security label length not being reset

nfs_readdir_page_filler() iterates over entries in a directory, reusing
the same security label buffer, but does not reset the buffer's length.
This causes decode_attr_security_label() to return -ERANGE if an entry's
security label is longer than the previous one's. This error, in
nfs4_decode_dirent(), only gets passed up as -EAGAIN, which causes another
failed attempt to copy into the buffer. The second error is ignored and
the remaining entries do not show up in ls, specifically the getdents64()
syscall.

Reproduce by creating multiple files in NFS and giving one of the later
files a longer security label. ls will not see that file nor any that are
added afterwards, though they will exist on the backend.

In nfs_readdir_page_filler(), reset security label buffer length before
every reuse

Signed-off-by: Jeffrey Mitchell <jeffrey.mitchell@starlab.io>
Fixes: b4487b935452 ("nfs: Fix getxattr kernel panic and memory overflow")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

show more ...

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through mar

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

show more ...

NFSv4.2: query the extended attribute access bits

RFC 8276 defines separate ACCESS bits for extended attribute checking.
Query them in nfs_do_access and opendata.

Signed-off-by: Frank van der Linde

NFSv4.2: query the extended attribute access bits

RFC 8276 defines separate ACCESS bits for extended attribute checking.
Query them in nfs_do_access and opendata.

Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

show more ...

nfs: define nfs_access_get_cached function

The only consumer of nfs_access_get_cached_rcu and nfs_access_cached
calls these static functions in order to first try RCU access, and
then locked access.

nfs: define nfs_access_get_cached function

The only consumer of nfs_access_get_cached_rcu and nfs_access_cached
calls these static functions in order to first try RCU access, and
then locked access.

Combine them in to a single function, and call that. Make this function
available to the rest of the NFS code.

Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

show more ...

NFS: Clean up process of marking inode stale.

Instead of the various open coded calls to set the NFS_INO_STALE bit
and call nfs_zap_caches(), consolidate them into a single function
nfs_set_inode_st

NFS: Clean up process of marking inode stale.

Instead of the various open coded calls to set the NFS_INO_STALE bit
and call nfs_zap_caches(), consolidate them into a single function
nfs_set_inode_stale().

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

show more ...

nfs: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
varia

nfs: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
int stuff;
struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

show more ...

NFS:remove redundant call to nfs_do_access

In function nfs_permission:
1. the rcu_read_lock and rcu_read_unlock around nfs_do_access
is unnecessary because the rcu critical data structure is already

NFS:remove redundant call to nfs_do_access

In function nfs_permission:
1. the rcu_read_lock and rcu_read_unlock around nfs_do_access
is unnecessary because the rcu critical data structure is already
protected in subsidiary function nfs_access_get_cached_rcu. No other
data structure needs rcu_read_lock in nfs_do_access.

2. call nfs_do_access once is enough, because:
2-1. when mask has MAY_NOT_BLOCK bit
The second call to nfs_do_access will not happen.

2-2. when mask has no MAY_NOT_BLOCK bit
The second call to nfs_do_access will happen if res == -ECHILD, which
means the first nfs_do_access goes out after statement if (!may_block).
The second call to nfs_do_access will go through this procedure once
again except continue the work after if (!may_block).
But above work can be performed by only one call to nfs_do_access
without mangling the mask flag.

Tested in x86_64
Signed-off-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

show more ...

NFS: Limit the size of the access cache by default

Currently, we have no real limit on the access cache size (we set it
to ULONG_MAX). That can lead to credentials getting pinned for a
very long tim

NFS: Limit the size of the access cache by default

Currently, we have no real limit on the access cache size (we set it
to ULONG_MAX). That can lead to credentials getting pinned for a
very long time on lots of files if you have a system with a lot of
memory.

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

show more ...

NFS: Use the 64-bit server readdir cookies when possible

When we're running as a 64-bit architecture and are not running in
32-bit compatibility mode, it is better to use the 64-bit readdir
cookies

NFS: Use the 64-bit server readdir cookies when possible

When we're running as a 64-bit architecture and are not running in
32-bit compatibility mode, it is better to use the 64-bit readdir
cookies that supplied by the server. Doing so improves the accuracy
of telldir()/seekdir(), particularly when the directory is changing,
for instance, when doing 'rm -rf'.

We still fall back to using the 32-bit offsets on 32-bit architectures
and when in compatibility mode.

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

show more ...

nfs: Fix nfs_access_get_cached_rcu() sparse error

This patch fixes the following sparse error:
fs/nfs/dir.c:2353:14: error: incompatible types in comparison expression (different address spaces):
fs

nfs: Fix nfs_access_get_cached_rcu() sparse error

This patch fixes the following sparse error:
fs/nfs/dir.c:2353:14: error: incompatible types in comparison expression (different address spaces):
fs/nfs/dir.c:2353:14: struct list_head [noderef] <asn:4> *
fs/nfs/dir.c:2353:14: struct list_head *

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik04@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

show more ...