lede/package/kernel/mac80211/patches/ath11k/0095-ath11k-use-cache-line-aligned-buffers-for-dbring.patch

92 lines
2.9 KiB
Diff

From bd77f6b1d7104cf6451399a7c67d08afecb9a7c7 Mon Sep 17 00:00:00 2001
From: Rameshkumar Sundaram <quic_ramess@quicinc.com>
Date: Tue, 2 Nov 2021 11:11:33 +0530
Subject: [PATCH 095/120] ath11k: use cache line aligned buffers for dbring
The DMA buffers of dbring which is used for spectral/cfr
starts at certain offset from original kmalloc() returned buffer.
This is not cache line aligned.
And also driver tries to access the data that is immediately before
this offset address (i.e. buff->paddr) after doing dma map.
This will cause cache line sharing issues and data corruption,
if CPU happen to write back cache after HW has dma'ed the data.
Fix this by mapping a cache line aligned buffer to dma.
Tested on: IPQ8074 hw2.0 AHB WLAN.HK.2.5.0.1-01100-QCAHKSWPL_SILICONZ-1
Signed-off-by: Rameshkumar Sundaram <quic_ramess@quicinc.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1635831693-15962-1-git-send-email-quic_ramess@quicinc.com
---
drivers/net/wireless/ath/ath11k/dbring.c | 16 ++++++++++++----
drivers/net/wireless/ath/ath11k/dbring.h | 2 +-
2 files changed, 13 insertions(+), 5 deletions(-)
--- a/drivers/net/wireless/ath/ath11k/dbring.c
+++ b/drivers/net/wireless/ath/ath11k/dbring.c
@@ -87,17 +87,23 @@ static int ath11k_dbring_fill_bufs(struc
req_entries = min(num_free, ring->bufs_max);
num_remain = req_entries;
align = ring->buf_align;
- size = sizeof(*buff) + ring->buf_sz + align - 1;
+ size = ring->buf_sz + align - 1;
while (num_remain > 0) {
- buff = kzalloc(size, GFP_ATOMIC);
+ buff = kzalloc(sizeof(*buff), GFP_ATOMIC);
if (!buff)
break;
+ buff->payload = kzalloc(size, GFP_ATOMIC);
+ if (!buff->payload) {
+ kfree(buff);
+ break;
+ }
ret = ath11k_dbring_bufs_replenish(ar, ring, buff);
if (ret) {
ath11k_warn(ar->ab, "failed to replenish db ring num_remain %d req_ent %d\n",
num_remain, req_entries);
+ kfree(buff->payload);
kfree(buff);
break;
}
@@ -282,7 +288,7 @@ int ath11k_dbring_buffer_release_event(s
srng = &ab->hal.srng_list[ring->refill_srng.ring_id];
num_entry = ev->fixed.num_buf_release_entry;
- size = sizeof(*buff) + ring->buf_sz + ring->buf_align - 1;
+ size = ring->buf_sz + ring->buf_align - 1;
num_buff_reaped = 0;
spin_lock_bh(&srng->lock);
@@ -319,7 +325,8 @@ int ath11k_dbring_buffer_release_event(s
ring->handler(ar, &handler_data);
}
- memset(buff, 0, size);
+ buff->paddr = 0;
+ memset(buff->payload, 0, size);
ath11k_dbring_bufs_replenish(ar, ring, buff);
}
@@ -346,6 +353,7 @@ void ath11k_dbring_buf_cleanup(struct at
idr_remove(&ring->bufs_idr, buf_id);
dma_unmap_single(ar->ab->dev, buff->paddr,
ring->buf_sz, DMA_FROM_DEVICE);
+ kfree(buff->payload);
kfree(buff);
}
--- a/drivers/net/wireless/ath/ath11k/dbring.h
+++ b/drivers/net/wireless/ath/ath11k/dbring.h
@@ -13,7 +13,7 @@
struct ath11k_dbring_element {
dma_addr_t paddr;
- u8 payload[0];
+ u8 *payload;
};
struct ath11k_dbring_data {