[PATCH net-next v2 2/4] NTB: ntb_transport: Use little-endian shared fields
From: Koichiro Den <hidden>
Date: 2026-08-17 06:49:32
Also in:
lkml
Subsystem:
ntb driver core, the rest · Maintainers:
Jon Mason, Dave Jiang, Allen Hubbe, Linus Torvalds
ntb_transport writes payload headers and the RX ring tail with
iowrite32(), but reads peer-written copies from coherent memory as native
integers. The values are therefore byte-swapped when read on a big-endian
system.
Mark the shared fields as __le32 and convert coherent-memory accesses
accordingly.
Fixes: 74465645cdb4 ("NTB: Fix Sparse Warnings")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Link: https://lore.kernel.org/r/20260815032932.151F11F000E9@smtp.kernel.org/
Signed-off-by: Koichiro Den <redacted>
---
Changes in v2:
- New patch. (Sashiko)
drivers/ntb/ntb_transport.c | 47 +++++++++++++++++++++----------------
1 file changed, 27 insertions(+), 20 deletions(-)
diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c
index d458a8b1de11..967a5ad38164 100644
--- a/drivers/ntb/ntb_transport.c
+++ b/drivers/ntb/ntb_transport.c@@ -132,7 +132,7 @@ struct ntb_queue_entry { }; struct ntb_rx_info { - unsigned int entry; + __le32 entry; }; struct ntb_transport_qp {
@@ -265,9 +265,9 @@ enum { }; struct ntb_payload_header { - unsigned int ver; - unsigned int len; - unsigned int flags; + __le32 ver; + __le32 len; + __le32 flags; }; enum {
@@ -514,7 +514,8 @@ static int ntb_qp_debugfs_stats_show(struct seq_file *s, void *v) seq_printf(s, "tx_err_no_buf - %llu\n", qp->tx_err_no_buf); seq_printf(s, "tx_mw - \t0x%p\n", qp->tx_mw); seq_printf(s, "tx_index (H) - \t%u\n", qp->tx_index); - seq_printf(s, "RRI (T) - \t%u\n", qp->remote_rx_info->entry); + seq_printf(s, "RRI (T) - \t%u\n", + le32_to_cpu(qp->remote_rx_info->entry)); seq_printf(s, "tx_max_entry - \t%u\n", qp->tx_max_entry); seq_printf(s, "free tx - \t%u\n", ntb_transport_tx_free_entry(qp)); seq_putc(s, '\n');
@@ -633,7 +634,7 @@ static int ntb_transport_setup_qp_mw(struct ntb_transport_ctx *nt, qp->rx_alloc_entry++; } - qp->remote_rx_info->entry = qp->rx_max_entry - 1; + qp->remote_rx_info->entry = cpu_to_le32(qp->rx_max_entry - 1); /* setup the hdr offsets with 0's */ for (i = 0; i < qp->rx_max_entry; i++) {
@@ -919,7 +920,7 @@ static void ntb_qp_link_down_reset(struct ntb_transport_qp *qp) { ntb_qp_link_context_reset(qp); if (qp->remote_rx_info) - qp->remote_rx_info->entry = qp->rx_max_entry - 1; + qp->remote_rx_info->entry = cpu_to_le32(qp->rx_max_entry - 1); } static void ntb_qp_link_cleanup(struct ntb_transport_qp *qp)
@@ -1445,7 +1446,7 @@ static void ntb_complete_rxc(struct ntb_transport_qp *qp) if (!(entry->flags & DESC_DONE_FLAG)) break; - entry->rx_hdr->flags = 0; + entry->rx_hdr->flags = cpu_to_le32(0); iowrite32(entry->rx_index, &qp->rx_info->entry); cb_data = entry->cb_data;
@@ -1609,13 +1610,15 @@ static int ntb_process_rxc(struct ntb_transport_qp *qp) { struct ntb_payload_header *hdr; struct ntb_queue_entry *entry; - unsigned int flags; void *offset; + u32 flags; + u32 len; + u32 ver; offset = qp->rx_buff + qp->rx_max_frame * qp->rx_index; hdr = offset + qp->rx_max_frame - sizeof(struct ntb_payload_header); - flags = READ_ONCE(hdr->flags); + flags = le32_to_cpu(READ_ONCE(hdr->flags)); if (!(flags & DESC_DONE_FLAG)) { dev_dbg(&qp->ndev->pdev->dev, "done flag not set\n"); qp->rx_ring_empty++;
@@ -1623,21 +1626,23 @@ static int ntb_process_rxc(struct ntb_transport_qp *qp) } dma_rmb(); + ver = le32_to_cpu(hdr->ver); + len = le32_to_cpu(hdr->len); dev_dbg(&qp->ndev->pdev->dev, "qp %d: RX ver %u len %d flags %x\n", - qp->qp_num, hdr->ver, hdr->len, flags); + qp->qp_num, ver, len, flags); if (flags & LINK_DOWN_FLAG) { dev_dbg(&qp->ndev->pdev->dev, "link down flag set\n"); ntb_qp_link_down(qp); - hdr->flags = 0; + hdr->flags = cpu_to_le32(0); return -EAGAIN; } - if (hdr->ver != (u32)qp->rx_pkts) { + if (ver != (u32)qp->rx_pkts) { dev_dbg(&qp->ndev->pdev->dev, "version mismatch, expected %llu - got %u\n", - qp->rx_pkts, hdr->ver); + qp->rx_pkts, ver); qp->rx_err_ver++; return -EIO; }
@@ -1652,10 +1657,10 @@ static int ntb_process_rxc(struct ntb_transport_qp *qp) entry->rx_hdr = hdr; entry->rx_index = qp->rx_index; - if (hdr->len > entry->len) { + if (len > entry->len) { dev_dbg(&qp->ndev->pdev->dev, "receive buffer overflow! Wanted %d got %d\n", - hdr->len, entry->len); + len, entry->len); qp->rx_err_oflow++; entry->len = -EIO;
@@ -1665,12 +1670,12 @@ static int ntb_process_rxc(struct ntb_transport_qp *qp) } else { dev_dbg(&qp->ndev->pdev->dev, "RX OK index %u ver %u size %d into buf size %d\n", - qp->rx_index, hdr->ver, hdr->len, entry->len); + qp->rx_index, ver, len, entry->len); - qp->rx_bytes += hdr->len; + qp->rx_bytes += len; qp->rx_pkts++; - entry->len = hdr->len; + entry->len = len; ntb_async_rx(entry, offset); }
@@ -2492,7 +2497,9 @@ EXPORT_SYMBOL_GPL(ntb_transport_max_size); unsigned int ntb_transport_tx_free_entry(struct ntb_transport_qp *qp) { unsigned int head = qp->tx_index; - unsigned int tail = qp->remote_rx_info->entry; + unsigned int tail; + + tail = le32_to_cpu(READ_ONCE(qp->remote_rx_info->entry)); return tail >= head ? tail - head : qp->tx_max_entry + tail - head; }
--
2.51.0