Merge branch 'iommufd/arm-smmuv3-nested' of iommu/linux into iommufd for-next

Common SMMUv3 patches for the following patches adding nesting, shared
branch with the iommu tree.

* 'iommufd/arm-smmuv3-nested' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/iommu/linux:
  iommu/arm-smmu-v3: Expose the arm_smmu_attach interface
  iommu/arm-smmu-v3: Implement IOMMU_HWPT_ALLOC_NEST_PARENT
  iommu/arm-smmu-v3: Support IOMMU_GET_HW_INFO via struct arm_smmu_hw_info
  iommu/arm-smmu-v3: Report IOMMU_CAP_ENFORCE_CACHE_COHERENCY for CANWBS
  ACPI/IORT: Support CANWBS memory access flag
  ACPICA: IORT: Update for revision E.f
  vfio: Remove VFIO_TYPE1_NESTING_IOMMU
  ...

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

1 files changed, 36 insertions, 18 deletions

diff --git a/fs/netfs/write_issue.c b/fs/netfs/write_issue.c
index 0929d9fd4ce7..bf6d507578e5 100644
--- a/fs/netfs/write_issue.c
+++ b/fs/netfs/write_issue.c
@@ -317,6 +317,7 @@ static int netfs_write_folio(struct netfs_io_request *wreq,
 	struct netfs_io_stream *stream;
 	struct netfs_group *fgroup; /* TODO: Use this with ceph */
 	struct netfs_folio *finfo;
+	size_t iter_off = 0;
 	size_t fsize = folio_size(folio), flen = fsize, foff = 0;
 	loff_t fpos = folio_pos(folio), i_size;
 	bool to_eof = false, streamw = false;
@@ -472,7 +473,12 @@ static int netfs_write_folio(struct netfs_io_request *wreq,
 		if (choose_s < 0)
 			break;
 		stream = &wreq->io_streams[choose_s];
-		wreq->io_iter.iov_offset = stream->submit_off;
+
+		/* Advance the iterator(s). */
+		if (stream->submit_off > iter_off) {
+			iov_iter_advance(&wreq->io_iter, stream->submit_off - iter_off);
+			iter_off = stream->submit_off;
+		}
 
 		atomic64_set(&wreq->issued_to, fpos + stream->submit_off);
 		stream->submit_extendable_to = fsize - stream->submit_off;
@@ -487,8 +493,8 @@ static int netfs_write_folio(struct netfs_io_request *wreq,
 			debug = true;
 	}
 
-	wreq->io_iter.iov_offset = 0;
-	iov_iter_advance(&wreq->io_iter, fsize);
+	if (fsize > iter_off)
+		iov_iter_advance(&wreq->io_iter, fsize - iter_off);
 	atomic64_set(&wreq->issued_to, fpos + fsize);
 
 	if (!debug)
@@ -503,6 +509,30 @@ static int netfs_write_folio(struct netfs_io_request *wreq,
 }
 
 /*
+ * End the issuing of writes, letting the collector know we're done.
+ */
+static void netfs_end_issue_write(struct netfs_io_request *wreq)
+{
+	bool needs_poke = true;
+
+	smp_wmb(); /* Write subreq lists before ALL_QUEUED. */
+	set_bit(NETFS_RREQ_ALL_QUEUED, &wreq->flags);
+
+	for (int s = 0; s < NR_IO_STREAMS; s++) {
+		struct netfs_io_stream *stream = &wreq->io_streams[s];
+
+		if (!stream->active)
+			continue;
+		if (!list_empty(&stream->subrequests))
+			needs_poke = false;
+		netfs_issue_write(wreq, stream);
+	}
+
+	if (needs_poke)
+		netfs_wake_write_collector(wreq, false);
+}
+
+/*
  * Write some of the pending data back to the server
  */
 int netfs_writepages(struct address_space *mapping,
@@ -553,10 +583,7 @@ int netfs_writepages(struct address_space *mapping,
 			break;
 	} while ((folio = writeback_iter(mapping, wbc, folio, &error)));
 
-	for (int s = 0; s < NR_IO_STREAMS; s++)
-		netfs_issue_write(wreq, &wreq->io_streams[s]);
-	smp_wmb(); /* Write lists before ALL_QUEUED. */
-	set_bit(NETFS_RREQ_ALL_QUEUED, &wreq->flags);
+	netfs_end_issue_write(wreq);
 
 	mutex_unlock(&ictx->wb_lock);
 
@@ -644,10 +671,7 @@ int netfs_end_writethrough(struct netfs_io_request *wreq, struct writeback_contr
 	if (writethrough_cache)
 		netfs_write_folio(wreq, wbc, writethrough_cache);
 
-	netfs_issue_write(wreq, &wreq->io_streams[0]);
-	netfs_issue_write(wreq, &wreq->io_streams[1]);
-	smp_wmb(); /* Write lists before ALL_QUEUED. */
-	set_bit(NETFS_RREQ_ALL_QUEUED, &wreq->flags);
+	netfs_end_issue_write(wreq);
 
 	mutex_unlock(&ictx->wb_lock);
 
@@ -693,13 +717,7 @@ int netfs_unbuffered_write(struct netfs_io_request *wreq, bool may_wait, size_t
 			break;
 	}
 
-	netfs_issue_write(wreq, upload);
-
-	smp_wmb(); /* Write lists before ALL_QUEUED. */
-	set_bit(NETFS_RREQ_ALL_QUEUED, &wreq->flags);
-	if (list_empty(&upload->subrequests))
-		netfs_wake_write_collector(wreq, false);
-
+	netfs_end_issue_write(wreq);
 	_leave(" = %d", error);
 	return error;
 }