[PATCH v2] dmaengine: ioat: fixing the wrong dma_dev->chancnt

From: Yajun Deng
Date: Tue Aug 15 2023 - 02:13:18 EST


The chancnt would be updated in __dma_async_device_channel_register(),
but it was assigned in ioat_enumerate_channels(). Therefore chancnt has
the wrong value.

Add chancnt member to the struct ioatdma_device, ioat_dma->chancnt
is used in ioat, dma_dev->chancnt is used in dmaengine.

Signed-off-by: Yajun Deng <yajun.deng@xxxxxxxxx>
---
V1 -> V2: add chancnt member to the struct ioatdma_device.
---
drivers/dma/ioat/dma.h | 1 +
drivers/dma/ioat/init.c | 19 ++++++++++---------
2 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h
index 35e06b382603..a180171087a8 100644
--- a/drivers/dma/ioat/dma.h
+++ b/drivers/dma/ioat/dma.h
@@ -74,6 +74,7 @@ struct ioatdma_device {
struct dca_provider *dca;
enum ioat_irq_mode irq_mode;
u32 cap;
+ int chancnt;

/* shadow version for CB3.3 chan reset errata workaround */
u64 msixtba0;
diff --git a/drivers/dma/ioat/init.c b/drivers/dma/ioat/init.c
index c4602bfc9c74..9c364e92cb82 100644
--- a/drivers/dma/ioat/init.c
+++ b/drivers/dma/ioat/init.c
@@ -420,7 +420,7 @@ int ioat_dma_setup_interrupts(struct ioatdma_device *ioat_dma)

msix:
/* The number of MSI-X vectors should equal the number of channels */
- msixcnt = ioat_dma->dma_dev.chancnt;
+ msixcnt = ioat_dma->chancnt;
for (i = 0; i < msixcnt; i++)
ioat_dma->msix_entries[i].entry = i;

@@ -511,7 +511,7 @@ static int ioat_probe(struct ioatdma_device *ioat_dma)
dma_cap_set(DMA_MEMCPY, dma->cap_mask);
dma->dev = &pdev->dev;

- if (!dma->chancnt) {
+ if (!ioat_dma->chancnt) {
dev_err(dev, "channel enumeration error\n");
goto err_setup_interrupts;
}
@@ -567,15 +567,16 @@ static void ioat_enumerate_channels(struct ioatdma_device *ioat_dma)
struct device *dev = &ioat_dma->pdev->dev;
struct dma_device *dma = &ioat_dma->dma_dev;
u8 xfercap_log;
+ int chancnt;
int i;

INIT_LIST_HEAD(&dma->channels);
- dma->chancnt = readb(ioat_dma->reg_base + IOAT_CHANCNT_OFFSET);
- dma->chancnt &= 0x1f; /* bits [4:0] valid */
- if (dma->chancnt > ARRAY_SIZE(ioat_dma->idx)) {
+ chancnt = readb(ioat_dma->reg_base + IOAT_CHANCNT_OFFSET);
+ chancnt &= 0x1f; /* bits [4:0] valid */
+ if (chancnt > ARRAY_SIZE(ioat_dma->idx)) {
dev_warn(dev, "(%d) exceeds max supported channels (%zu)\n",
- dma->chancnt, ARRAY_SIZE(ioat_dma->idx));
- dma->chancnt = ARRAY_SIZE(ioat_dma->idx);
+ chancnt, ARRAY_SIZE(ioat_dma->idx));
+ chancnt = ARRAY_SIZE(ioat_dma->idx);
}
xfercap_log = readb(ioat_dma->reg_base + IOAT_XFERCAP_OFFSET);
xfercap_log &= 0x1f; /* bits [4:0] valid */
@@ -583,7 +584,7 @@ static void ioat_enumerate_channels(struct ioatdma_device *ioat_dma)
return;
dev_dbg(dev, "%s: xfercap = %d\n", __func__, 1 << xfercap_log);

- for (i = 0; i < dma->chancnt; i++) {
+ for (i = 0; i < chancnt; i++) {
ioat_chan = kzalloc(sizeof(*ioat_chan), GFP_KERNEL);
if (!ioat_chan)
break;
@@ -596,7 +597,7 @@ static void ioat_enumerate_channels(struct ioatdma_device *ioat_dma)
break;
}
}
- dma->chancnt = i;
+ ioat_dma->chancnt = i;
}

/**
--
2.25.1