kernel/linux.git/fs/netfs/write_issue.c, branch v6.18.44

netfs: handle single writeback rolling buffer allocation failure

2026-08-09T18:25:05+00:00

[ Upstream commit 37a1c535c80c67d98668d190c7432f9ebda43310 ] netfs_write_folio_single() takes an extra folio reference before appending the folio to the rolling buffer. rolling_buffer_append() can fail if it cannot allocate another folio_queue. Check the return value and drop the extra folio reference before returning the error. Fixes: 49866ce7ea8d ("netfs: Add support for caching single monolithic objects such as AFS dirs") Signed-off-by: Yichong Chen Signed-off-by: David Howells Link: https://patch.msgid.link/20260727130716.1099906-3-dhowells@redhat.com cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner (Amutable) Signed-off-by: Sasha Levin

netfs: Fix folio state after ENOMEM whilst under writeback iteration

2026-07-24T14:16:45+00:00

[ Upstream commit b6a713fd34b9498ee2164d5d3e8460732a392efc ] Fix the state of the current folio when ENOMEM occurs during writeback iteration. The folio needs to be redirtied and unlocked before the terminal writeback_iter() is invoked. Fixes: 06fa229ceb36 ("netfs: Abstract out a rolling folio buffer implementation") Link: https://sashiko.dev/#/patchset/20260619140646.2633762-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260625140640.3116900-15-dhowells@redhat.com cc: Paulo Alcantara cc: Matthew Wilcox cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner (Amutable) Signed-off-by: Sasha Levin

netfs: Fix writeback error handling

2026-07-24T14:16:45+00:00

[ Upstream commit ac5f95ac5d6d0f4c567b8b642825705a2bf0d79e ] Fix the error handling in writeback_iter() loop. If an error occurs, writeback_iter() needs to be called again with *error set to the error so that it can clean up iteration state. Further, the current folio needs unlocking and redirtying. Fixes: 288ace2f57c9 ("netfs: New writeback implementation") Link: https://sashiko.dev/#/patchset/20260619140646.2633762-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260625140640.3116900-14-dhowells@redhat.com cc: Paulo Alcantara cc: Matthew Wilcox cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner (Amutable) Signed-off-by: Sasha Levin

netfs: Fix writethrough to use collection offload

2026-07-24T14:16:45+00:00

[ Upstream commit ba6a9f6533c77c628eef0c0c5c19cd316e2be1b4 ] Fix writethrough write to set NETFS_RREQ_OFFLOAD_COLLECTION on the request so that collection is processed asynchronously rather than only right at the end - and also so that asynchronous O_SYNC writes get collected at all. Fixes: 288ace2f57c9 ("netfs: New writeback implementation") Closes: https://sashiko.dev/#/patchset/20260616100821.2062304-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260625140640.3116900-13-dhowells@redhat.com cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner (Amutable) Signed-off-by: Sasha Levin

netfs: Fix netfs_create_write_req() to handle async cache object creation

2026-07-24T14:16:45+00:00

[ Upstream commit dbd6f56d975b23241b7bbb11bb8f562af548a0aa ] netfs_create_write_req() will skip caching if the fscache cookie is disabled, but this is a problem because async cache object creation might not have got far enough yet that has been enabled - thereby causing the call to fscache_begin_write_operation() to be skipped. Fix this by removing the checks on the cookie and delegating this to fscache_begin_write_operation(). Fixes: 7b589a9b45ae ("netfs: Fix handling of USE_PGPRIV2 and WRITE_TO_CACHE flags") Closes: https://sashiko.dev/#/patchset/20260624115737.2964520-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260625140640.3116900-3-dhowells@redhat.com cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner (Amutable) Signed-off-by: Sasha Levin

netfs, afs: Fix write skipping in dir/link writepages

2026-06-01T15:50:57+00:00

[ Upstream commit 9871938f99cc6cb266a77265491660e2375271f5 ] Fix netfs_write_single() and afs_single_writepages() to better handle a write that would be skipped due to lock contention and WB_SYNC_NONE by returning 1 from netfs_write_single() if it skipped and making afs_single_writepages() skip also. If a skip occurs, the inode must be re-marked as the VFS may have cleared the mark. This is really only theoretical for directories in netfs_write_single() as the only path to that is through afs_single_writepages() that takes the ->validate_lock around it, thereby serialising it. Fixes: 6dd80936618c ("afs: Use netfslib for directories") Signed-off-by: David Howells Link: https://patch.msgid.link/20260512123404.719402-24-dhowells@redhat.com cc: Marc Dionne cc: linux-afs@lists.infradead.org cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

netfs: Fix potential deadlock in write-through mode

2026-06-01T15:50:56+00:00

[ Upstream commit b6a4ae1634b3ad2aaa05222e53d36da532852faf ] Fix netfs_advance_writethrough() to always unlock the supplied folio and to mark it dirty if it isn't yet written to the end. Unfortunately, it can't be marked for writeback until the folio is done with as that may cause a deadlock against mmapped reads and writes. Even though it has been marked dirty, premature writeback can't occur as the caller is holding both inode->i_rwsem (which will prevent concurrent truncation, fallocation, DIO and other writes) and ictx->wb_lock (which will cause flushing to wait and writeback to skip or wait). Note that this may be easier to deal with once the queuing of folios is split from the generation of subrequests. Fixes: 288ace2f57c9 ("netfs: New writeback implementation") Closes: https://sashiko.dev/#/patchset/20260427154639.180684-1-dhowells%40redhat.com Signed-off-by: David Howells Link: https://patch.msgid.link/20260512123404.719402-15-dhowells@redhat.com cc: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

netfs: Fix the handling of stream->front by removing it

2026-04-02T11:23:33+00:00

[ Upstream commit 0e764b9d46071668969410ec5429be0e2f38c6d3 ] The netfs_io_stream::front member is meant to point to the subrequest currently being collected on a stream, but it isn't actually used this way by direct write (which mostly ignores it). However, there's a tracepoint which looks at it. Further, stream->front is actually redundant with stream->subrequests.next. Fix the potential problem in the direct code by just removing the member and using stream->subrequests.next instead, thereby also simplifying the code. Fixes: a0b4c7a49137 ("netfs: Fix unbuffered/DIO writes to dispatch subrequests in strict sequence") Reported-by: Paulo Alcantara Signed-off-by: David Howells Link: https://patch.msgid.link/4158599.1774426817@warthog.procyon.org.uk Reviewed-by: Paulo Alcantara (Red Hat) cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

netfs: Fix unbuffered/DIO writes to dispatch subrequests in strict sequence

2026-03-12T11:09:49+00:00

[ Upstream commit a0b4c7a49137ed21279f354eb59f49ddae8dffc2 ] Fix netfslib such that when it's making an unbuffered or DIO write, to make sure that it sends each subrequest strictly sequentially, waiting till the previous one is 'committed' before sending the next so that we don't have pieces landing out of order and potentially leaving a hole if an error occurs (ENOSPC for example). This is done by copying in just those bits of issuing, collecting and retrying subrequests that are necessary to do one subrequest at a time. Retrying, in particular, is simpler because if the current subrequest needs retrying, the source iterator can just be copied again and the subrequest prepped and issued again without needing to be concerned about whether it needs merging with the previous or next in the sequence. Note that the issuing loop waits for a subrequest to complete right after issuing it, but this wait could be moved elsewhere allowing preparatory steps to be performed whilst the subrequest is in progress. In particular, once content encryption is available in netfslib, that could be done whilst waiting, as could cleanup of buffers that have been completed. Fixes: 153a9961b551 ("netfs: Implement unbuffered/DIO write support") Signed-off-by: David Howells Link: https://patch.msgid.link/58526.1772112753@warthog.procyon.org.uk Tested-by: Steve French Reviewed-by: Paulo Alcantara (Red Hat) cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

netfs: when subreq is marked for retry, do not check if it faced an error

2026-03-04T12:19:32+00:00

[ Upstream commit 82e8885bd7633a36ee9050e6d7f348a4155eed5f ] The *_subreq_terminated functions today only process the NEED_RETRY flag when the subreq was successful or failed with EAGAIN error. However, there could be other retriable errors for network filesystems. Avoid this by processing the NEED_RETRY irrespective of the error code faced by the subreq. If it was specifically marked for retry, the error code must not matter. Acked-by: David Howells Signed-off-by: Shyam Prasad N Signed-off-by: Steve French Signed-off-by: Sasha Levin