Add support for ITER_BVECQ to smbdirect_map_sges_from_iter().
Signed-off-by: David Howells <[email protected]>
Acked-by: Stefan Metzmacher <[email protected]>
cc: Paulo Alcantara <[email protected]>
cc: Matthew Wilcox <[email protected]>
cc: Christoph Hellwig <[email protected]>
cc: Steve French <[email protected]>
cc: Shyam Prasad N <[email protected]>
cc: Tom Talpey <[email protected]>
cc: [email protected]
cc: [email protected]
cc: [email protected]
---
fs/smb/smbdirect/connection.c | 66 +++++++++++++++++++++++++++++++++++
1 file changed, 66 insertions(+)
diff --git a/fs/smb/smbdirect/connection.c b/fs/smb/smbdirect/connection.c
index 8adf58097534..4d2a1700104e 100644
--- a/fs/smb/smbdirect/connection.c
+++ b/fs/smb/smbdirect/connection.c
@@ -5,6 +5,7 @@
*/
#include "internal.h"
+#include <linux/bvecq.h>
#include <linux/folio_queue.h>
struct smbdirect_map_sges {
@@ -2006,6 +2007,68 @@ static ssize_t smbdirect_map_sges_from_bvec(struct
iov_iter *iter,
return ret;
}
+/*
+ * Extract memory fragments from a BVECQ-class iterator and add them to an RDMA
+ * list. The fragments are not pinned.
+ */
+static ssize_t smbdirect_map_sges_from_bvecq(struct iov_iter *iter,
+ struct smbdirect_map_sges *state,
+ ssize_t maxsize)
+{
+ const struct bvecq *bq = iter->bvecq;
+ unsigned int slot = iter->bvecq_slot;
+ ssize_t extracted = 0;
+ size_t offset = iter->iov_offset;
+
+ maxsize = umin(maxsize, iov_iter_count(iter));
+
+ do {
+ struct bio_vec *bv;
+ size_t bsize;
+
+ while (slot >= bq->nr_slots) {
+ if (!bq->next) {
+ if (WARN_ON_ONCE(maxsize > 0))
+ return -EIO;
+ goto out;
+ }
+ bq = bq->next;
+ slot = 0;
+ }
+
+ bv = &bq->bv[slot];
+ bsize = bv->bv_len;
+
+ if (offset < bsize) {
+ size_t part = umin(maxsize, bsize - offset);
+ bool ok;
+
+ ok = smbdirect_map_sges_single_page(state,
+ bv->bv_page,
+ bv->bv_offset +
offset,
+ part);
+ if (!ok)
+ return -EIO;
+
+ offset += part;
+ extracted += part;
+ maxsize -= part;
+ }
+
+ if (offset >= bsize) {
+ offset = 0;
+ slot++;
+ }
+ } while (state->num_sge < state->max_sge && maxsize > 0);
+
+out:
+ iter->bvecq = bq;
+ iter->bvecq_slot = slot;
+ iter->iov_offset = offset;
+ iter->count -= extracted;
+ return extracted;
+}
+
/*
* Extract fragments from a KVEC-class iterator and add them to an ib_sge list.
* This can deal with vmalloc'd buffers as well as kmalloc'd or static buffers.
@@ -2155,6 +2218,9 @@ static ssize_t smbdirect_map_sges_from_iter(struct
iov_iter *iter, size_t len,
case ITER_BVEC:
ret = smbdirect_map_sges_from_bvec(iter, state, len);
break;
+ case ITER_BVECQ:
+ ret = smbdirect_map_sges_from_bvecq(iter, state, len);
+ break;
case ITER_KVEC:
ret = smbdirect_map_sges_from_kvec(iter, state, len);
break;
