kernel/git/stable/linux.git/fs/netfs/io.c, branch master

netfs: Remove fs/netfs/io.c

2024-09-12T10:20:41+00:00

Remove fs/netfs/io.c as it is no longer used. Signed-off-by: David Howells cc: Jeff Layton cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20240814203850.2240469-21-dhowells@redhat.com/ # v2 Signed-off-by: Christian Brauner

netfs: Set the request work function upon allocation

2024-09-05T09:00:42+00:00

Set the work function in the netfs_io_request work_struct when we allocate the request rather than doing this later. This reduces the number of places we need to set it in future code. Signed-off-by: David Howells cc: Jeff Layton cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20240814203850.2240469-11-dhowells@redhat.com/ # v2 Signed-off-by: Christian Brauner

netfs: Move max_len/max_nr_segs from netfs_io_subrequest to netfs_io_stream

2024-09-05T09:00:41+00:00

Move max_len/max_nr_segs from struct netfs_io_subrequest to struct netfs_io_stream as we only issue one subreq at a time and then don't need these values again for that subreq unless and until we have to retry it - in which case we want to renegotiate them. Signed-off-by: David Howells cc: Jeff Layton cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Link: https://lore.kernel.org/r/20240814203850.2240469-8-dhowells@redhat.com/ # v2 Signed-off-by: Christian Brauner

netfs, cifs: Fix handling of short DIO read

2024-08-28T12:47:36+00:00

Short DIO reads, particularly in relation to cifs, are not being handled correctly by cifs and netfslib. This can be tested by doing a DIO read of a file where the size of read is larger than the size of the file. When it crosses the EOF, it gets a short read and this gets retried, and in the case of cifs, the retry read fails, with the failure being translated to ENODATA. Fix this by the following means: (1) Add a flag, NETFS_SREQ_HIT_EOF, for the filesystem to set when it detects that the read did hit the EOF. (2) Make the netfslib read assessment stop processing subrequests when it encounters one with that flag set. (3) Return rreq->transferred, the accumulated contiguous amount read to that point, to userspace for a DIO read. (4) Make cifs set the flag and clear the error if the read RPC returned ENODATA. (5) Make cifs set the flag and clear the error if a short read occurred without error and the read-to file position is now at the remote inode size. Fixes: 69c3c023af25 ("cifs: Implement netfslib hooks") Signed-off-by: David Howells cc: Steve French cc: Paulo Alcantara cc: Jeff Layton cc: linux-cifs@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Steve French

cifs: Fix lack of credit renegotiation on read retry

2024-08-28T12:47:36+00:00

When netfslib asks cifs to issue a read operation, it prefaces this with a call to ->clamp_length() which cifs uses to negotiate credits, providing receive capacity on the server; however, in the event that a read op needs reissuing, netfslib doesn't call ->clamp_length() again as that could shorten the subrequest, leaving a gap. This causes the retried read to be done with zero credits which causes the server to reject it with STATUS_INVALID_PARAMETER. This is a problem for a DIO read that is requested that would go over the EOF. The short read will be retried, causing EINVAL to be returned to the user when it fails. Fix this by making cifs_req_issue_read() negotiate new credits if retrying (NETFS_SREQ_RETRYING now gets set in the read side as well as the write side in this instance). This isn't sufficient, however: the new credits might not be sufficient to complete the remainder of the read, so also add an additional field, rreq->actual_len, that holds the actual size of the op we want to perform without having to alter subreq->len. We then rely on repeated short reads being retried until we finish the read or reach the end of file and make a zero-length read. Also fix a couple of places where the subrequest start and length need to be altered by the amount so far transferred when being used. Fixes: 69c3c023af25 ("cifs: Implement netfslib hooks") Signed-off-by: David Howells cc: Steve French cc: Paulo Alcantara cc: Jeff Layton cc: linux-cifs@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Steve French

netfs: Fix missing iterator reset on retry of short read

2024-08-24T14:09:17+00:00

Fix netfs_rreq_perform_resubmissions() to reset before retrying a short read, otherwise the wrong part of the output buffer will be used. Fixes: 92b6cc5d1e7c ("netfs: Add iov_iters to (sub)requests to describe various buffers") Signed-off-by: David Howells Link: https://lore.kernel.org/r/20240823200819.532106-6-dhowells@redhat.com cc: Steve French cc: Paulo Alcantara cc: Jeff Layton cc: linux-cifs@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner

9p: Fix DIO read through netfs

2024-08-13T11:53:09+00:00

If a program is watching a file on a 9p mount, it won't see any change in size if the file being exported by the server is changed directly in the source filesystem, presumably because 9p doesn't have change notifications, and because netfs skips the reads if the file is empty. Fix this by attempting to read the full size specified when a DIO read is requested (such as when 9p is operating in unbuffered mode) and dealing with a short read if the EOF was less than the expected read. To make this work, filesystems using netfslib must not set NETFS_SREQ_CLEAR_TAIL if performing a DIO read where that read hit the EOF. I don't want to mandatorily clear this flag in netfslib for DIO because, say, ceph might make a read from an object that is not completely filled, but does not reside at the end of file - and so we need to clear the excess. This can be tested by watching an empty file over 9p within a VM (such as in the ktest framework): while true; do read content; if [ -n "$content" ]; then echo $content; break; fi; done < /host/tmp/foo then writing something into the empty file. The watcher should immediately display the file content and break out of the loop. Without this fix, it remains in the loop indefinitely. Fixes: 80105ed2fd27 ("9p: Use netfslib read/write_iter") Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218916 Signed-off-by: David Howells Link: https://lore.kernel.org/r/1229195.1723211769@warthog.procyon.org.uk cc: Eric Van Hensbergen cc: Latchesar Ionkov cc: Christian Schoenebeck cc: Marc Dionne cc: Ilya Dryomov cc: Steve French cc: Paulo Alcantara cc: Trond Myklebust cc: v9fs@lists.linux.dev cc: linux-afs@lists.infradead.org cc: ceph-devel@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: linux-nfs@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Dominique Martinet Signed-off-by: Christian Brauner

netfs, ceph: Revert "netfs: Remove deprecated use of PG_private_2 as a second writeback flag"

2024-08-12T20:03:27+00:00

This reverts commit ae678317b95e760607c7b20b97c9cd4ca9ed6e1a. Revert the patch that removes the deprecated use of PG_private_2 in netfslib for the moment as Ceph is actually still using this to track data copied to the cache. Fixes: ae678317b95e ("netfs: Remove deprecated use of PG_private_2 as a second writeback flag") Reported-by: Max Kellermann Signed-off-by: David Howells cc: Ilya Dryomov cc: Xiubo Li cc: Jeff Layton cc: Matthew Wilcox cc: ceph-devel@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org cc: linux-mm@kvack.org https: //lore.kernel.org/r/3575457.1722355300@warthog.procyon.org.uk Signed-off-by: Christian Brauner

netfs: Revert "netfs: Switch debug logging to pr_debug()"

2024-07-24T08:15:37+00:00

Revert commit 163eae0fb0d4c610c59a8de38040f8e12f89fd43 to get back the original operation of the debugging macros. Signed-off-by: David Howells Link: https://lore.kernel.org/r/20240608151352.22860-2-ukleinek@kernel.org Link: https://lore.kernel.org/r/1410685.1721333252@warthog.procyon.org.uk cc: Uwe Kleine-König cc: Christian Brauner cc: Jeff Layton cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner

netfs: Switch debug logging to pr_debug()

2024-06-12T12:25:41+00:00

Instead of inventing a custom way to conditionally enable debugging, just make use of pr_debug(), which also has dynamic debugging facilities and is more likely known to someone who hunts a problem in the netfs code. Also drop the module parameter netfs_debug which didn't have any effect without further source changes. (The variable netfs_debug was only used in #ifdef blocks for cpp vars that don't exist; Note that CONFIG_NETFS_DEBUG isn't settable via kconfig, a variable with that name never existed in the mainline and is probably just taken over (and renamed) from similar custom debug logging implementations.) Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20240608151352.22860-2-ukleinek@kernel.org Signed-off-by: Christian Brauner