[PATCH V8 1/5] dma-mapping: Rework dma_get_cache_alignment()

From: Huacai Chen
Date: Tue Oct 17 2017 - 04:04:58 EST

Make dma_get_cache_alignment() to accept a 'dev' argument. As a result,
it can return different alignments due to different devices' I/O cache
coherency.

Currently, ARM/ARM64 and MIPS support coherent & noncoherent devices
co-exist. This may be extended in the future, so add a new function
pointer (i.e, get_cache_alignment) in 'struct dma_map_ops' as a generic
solution.

Cc: stable@xxxxxxxxxxxxxxx
Cc: Michael S. Tsirkin <mst@xxxxxxxxxxxxxx>
Cc: Pawel Osciak <pawel@xxxxxxxxxx>
Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Cc: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
Cc: Michael Chan <michael.chan@xxxxxxxxxxxx>
Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Cc: Ivan Mikhaylov <ivan@xxxxxxxxxx>
Cc: Tariq Toukan <tariqt@xxxxxxxxxxxx>
Cc: Andy Gross <agross@xxxxxxxxxxxxxx>
Cc: Mark A. Greer <mgreer@xxxxxxxxxxxxxxx>
Cc: Robert Baldyga <r.baldyga@xxxxxxxxxxxxx>
Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Signed-off-by: Huacai Chen <chenhc@xxxxxxxxxx>
---
drivers/infiniband/hw/mthca/mthca_main.c | 2 +-
drivers/media/v4l2-core/videobuf2-dma-contig.c | 2 +-
drivers/net/ethernet/broadcom/b44.c | 8 +++----
drivers/net/ethernet/ibm/emac/core.c | 22 ++++++++++-------
drivers/net/ethernet/ibm/emac/core.h | 6 ++---
drivers/net/ethernet/mellanox/mlx4/main.c | 2 +-
drivers/spi/spi-qup.c | 4 ++--
drivers/tty/serial/mpsc.c | 33 ++++++++++++++++++--------
drivers/tty/serial/samsung.c | 14 +++++------
include/linux/dma-mapping.h | 17 +++++++++----
10 files changed, 68 insertions(+), 42 deletions(-)

diff --git a/drivers/infiniband/hw/mthca/mthca_main.c b/drivers/infiniband/hw/mthca/mthca_main.c
index e36a9bc..078fe8d 100644
--- a/drivers/infiniband/hw/mthca/mthca_main.c
+++ b/drivers/infiniband/hw/mthca/mthca_main.c
@@ -416,7 +416,7 @@ static int mthca_init_icm(struct mthca_dev *mdev,

/* CPU writes to non-reserved MTTs, while HCA might DMA to reserved mtts */
mdev->limits.reserved_mtts = ALIGN(mdev->limits.reserved_mtts * mdev->limits.mtt_seg_size,
- dma_get_cache_alignment()) / mdev->limits.mtt_seg_size;
+ dma_get_cache_alignment(&mdev->pdev->dev)) / mdev->limits.mtt_seg_size;

mdev->mr_table.mtt_table = mthca_alloc_icm_table(mdev, init_hca->mtt_base,
mdev->limits.mtt_seg_size,
diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c
index 9f389f3..1f6a9b7 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-contig.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c
@@ -484,7 +484,7 @@ static void *vb2_dc_get_userptr(struct device *dev, unsigned long vaddr,
int ret = 0;
struct sg_table *sgt;
unsigned long contig_size;
- unsigned long dma_align = dma_get_cache_alignment();
+ unsigned long dma_align = dma_get_cache_alignment(dev);

/* Only cache aligned DMA transfers are reliable */
if (!IS_ALIGNED(vaddr | size, dma_align)) {
diff --git a/drivers/net/ethernet/broadcom/b44.c b/drivers/net/ethernet/broadcom/b44.c
index a1125d1..2f6ffe5 100644
--- a/drivers/net/ethernet/broadcom/b44.c
+++ b/drivers/net/ethernet/broadcom/b44.c
@@ -2344,6 +2344,10 @@ static int b44_init_one(struct ssb_device *sdev,
struct net_device *dev;
struct b44 *bp;
int err;
+ unsigned int dma_desc_align_size = dma_get_cache_alignment(sdev->dma_dev);
+
+ /* Setup paramaters for syncing RX/TX DMA descriptors */
+ dma_desc_sync_size = max_t(unsigned int, dma_desc_align_size, sizeof(struct dma_desc));

instance++;

@@ -2587,12 +2591,8 @@ static inline void b44_pci_exit(void)

static int __init b44_init(void)
{
- unsigned int dma_desc_align_size = dma_get_cache_alignment();
int err;

- /* Setup paramaters for syncing RX/TX DMA descriptors */
- dma_desc_sync_size = max_t(unsigned int, dma_desc_align_size, sizeof(struct dma_desc));
-
err = b44_pci_init();
if (err)
return err;
diff --git a/drivers/net/ethernet/ibm/emac/core.c b/drivers/net/ethernet/ibm/emac/core.c
index 7feff24..b0c5319 100644
--- a/drivers/net/ethernet/ibm/emac/core.c
+++ b/drivers/net/ethernet/ibm/emac/core.c
@@ -1030,8 +1030,9 @@ static int emac_set_mac_address(struct net_device *ndev, void *sa)

static int emac_resize_rx_ring(struct emac_instance *dev, int new_mtu)
{
- int rx_sync_size = emac_rx_sync_size(new_mtu);
- int rx_skb_size = emac_rx_skb_size(new_mtu);
+ struct device *dma_dev = &dev->ofdev->dev;
+ int rx_skb_size = emac_rx_skb_size(dma_dev, new_mtu);
+ int rx_sync_size = emac_rx_sync_size(dma_dev, new_mtu);
int i, ret = 0;
int mr1_jumbo_bit_change = 0;

@@ -1115,20 +1116,21 @@ static int emac_resize_rx_ring(struct emac_instance *dev, int new_mtu)
static int emac_change_mtu(struct net_device *ndev, int new_mtu)
{
struct emac_instance *dev = netdev_priv(ndev);
+ struct device *dma_dev = &dev->ofdev->dev;
int ret = 0;

DBG(dev, "change_mtu(%d)" NL, new_mtu);

if (netif_running(ndev)) {
/* Check if we really need to reinitialize RX ring */
- if (emac_rx_skb_size(ndev->mtu) != emac_rx_skb_size(new_mtu))
+ if (emac_rx_skb_size(dma_dev, ndev->mtu) != emac_rx_skb_size(dma_dev, new_mtu))
ret = emac_resize_rx_ring(dev, new_mtu);
}

if (!ret) {
ndev->mtu = new_mtu;
- dev->rx_skb_size = emac_rx_skb_size(new_mtu);
- dev->rx_sync_size = emac_rx_sync_size(new_mtu);
+ dev->rx_skb_size = emac_rx_skb_size(dma_dev, new_mtu);
+ dev->rx_sync_size = emac_rx_sync_size(dma_dev, new_mtu);
}

return ret;
@@ -1171,6 +1173,7 @@ static void emac_clean_rx_ring(struct emac_instance *dev)
static inline int emac_alloc_rx_skb(struct emac_instance *dev, int slot,
gfp_t flags)
{
+ struct device *dma_dev = &dev->ofdev->dev;
struct sk_buff *skb = alloc_skb(dev->rx_skb_size, flags);
if (unlikely(!skb))
return -ENOMEM;
@@ -1649,11 +1652,12 @@ static inline void emac_recycle_rx_skb(struct emac_instance *dev, int slot,
int len)
{
struct sk_buff *skb = dev->rx_skb[slot];
+ struct device *dma_dev = &dev->ofdev->dev;

DBG2(dev, "recycle %d %d" NL, slot, len);

if (len)
- dma_map_single(&dev->ofdev->dev, skb->data - 2,
+ dma_map_single(dma_dev, skb->data - 2,
EMAC_DMA_ALIGN(len + 2), DMA_FROM_DEVICE);

dev->rx_desc[slot].data_len = 0;
@@ -1727,6 +1731,7 @@ static int emac_poll_rx(void *param, int budget)
{
struct emac_instance *dev = param;
int slot = dev->rx_slot, received = 0;
+ struct device *dma_dev = &dev->ofdev->dev;

DBG2(dev, "poll_rx(%d)" NL, budget);

@@ -2998,6 +3003,7 @@ static int emac_probe(struct platform_device *ofdev)
struct emac_instance *dev;
struct device_node *np = ofdev->dev.of_node;
struct device_node **blist = NULL;
+ struct device *dma_dev = &ofdev->dev;
int err, i;

/* Skip unused/unwired EMACS. We leave the check for an unused
@@ -3077,8 +3083,8 @@ static int emac_probe(struct platform_device *ofdev)
np, dev->mal_dev->dev.of_node);
goto err_rel_deps;
}
- dev->rx_skb_size = emac_rx_skb_size(ndev->mtu);
- dev->rx_sync_size = emac_rx_sync_size(ndev->mtu);
+ dev->rx_skb_size = emac_rx_skb_size(dma_dev, ndev->mtu);
+ dev->rx_sync_size = emac_rx_sync_size(dma_dev, ndev->mtu);

/* Get pointers to BD rings */
dev->tx_desc =
diff --git a/drivers/net/ethernet/ibm/emac/core.h b/drivers/net/ethernet/ibm/emac/core.h
index 369de2c..68548a0 100644
--- a/drivers/net/ethernet/ibm/emac/core.h
+++ b/drivers/net/ethernet/ibm/emac/core.h
@@ -68,20 +68,20 @@ static inline int emac_rx_size(int mtu)
return mal_rx_size(ETH_DATA_LEN + EMAC_MTU_OVERHEAD);
}

-#define EMAC_DMA_ALIGN(x) ALIGN((x), dma_get_cache_alignment())
+#define EMAC_DMA_ALIGN(x) ALIGN((x), dma_get_cache_alignment(dma_dev))

#define EMAC_RX_SKB_HEADROOM \
EMAC_DMA_ALIGN(CONFIG_IBM_EMAC_RX_SKB_HEADROOM)

/* Size of RX skb for the given MTU */
-static inline int emac_rx_skb_size(int mtu)
+static inline int emac_rx_skb_size(struct device *dma_dev, int mtu)
{
int size = max(mtu + EMAC_MTU_OVERHEAD, emac_rx_size(mtu));
return EMAC_DMA_ALIGN(size + 2) + EMAC_RX_SKB_HEADROOM;
}

/* RX DMA sync size */
-static inline int emac_rx_sync_size(int mtu)
+static inline int emac_rx_sync_size(struct device *dma_dev, int mtu)
{
return EMAC_DMA_ALIGN(emac_rx_size(mtu) + 2);
}
diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index e61c99e..bc146dd 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -1660,7 +1660,7 @@ static int mlx4_init_icm(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap,
*/
dev->caps.reserved_mtts =
ALIGN(dev->caps.reserved_mtts * dev->caps.mtt_entry_sz,
- dma_get_cache_alignment()) / dev->caps.mtt_entry_sz;
+ dma_get_cache_alignment(&dev->persist->pdev->dev)) / dev->caps.mtt_entry_sz;

err = mlx4_init_icm_table(dev, &priv->mr_table.mtt_table,
init_hca->mtt_base,
diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c
index 974a8ce..e6da66e 100644
--- a/drivers/spi/spi-qup.c
+++ b/drivers/spi/spi-qup.c
@@ -862,7 +862,7 @@ static bool spi_qup_can_dma(struct spi_master *master, struct spi_device *spi,
struct spi_transfer *xfer)
{
struct spi_qup *qup = spi_master_get_devdata(master);
- size_t dma_align = dma_get_cache_alignment();
+ size_t dma_align = dma_get_cache_alignment(qup->dev);
int n_words;

if (xfer->rx_buf) {
@@ -1038,7 +1038,7 @@ static int spi_qup_probe(struct platform_device *pdev)
master->transfer_one = spi_qup_transfer_one;
master->dev.of_node = pdev->dev.of_node;
master->auto_runtime_pm = true;
- master->dma_alignment = dma_get_cache_alignment();
+ master->dma_alignment = dma_get_cache_alignment(dev);
master->max_dma_len = SPI_MAX_XFER;

platform_set_drvdata(pdev, master);
diff --git a/drivers/tty/serial/mpsc.c b/drivers/tty/serial/mpsc.c
index 67ffecc..c708457 100644
--- a/drivers/tty/serial/mpsc.c
+++ b/drivers/tty/serial/mpsc.c
@@ -81,19 +81,19 @@
* Number of Tx & Rx descriptors must be powers of 2.
*/
#define MPSC_RXR_ENTRIES 32
-#define MPSC_RXRE_SIZE dma_get_cache_alignment()
+#define MPSC_RXRE_SIZE dma_get_cache_alignment(dma_dev)
#define MPSC_RXR_SIZE (MPSC_RXR_ENTRIES * MPSC_RXRE_SIZE)
-#define MPSC_RXBE_SIZE dma_get_cache_alignment()
+#define MPSC_RXBE_SIZE dma_get_cache_alignment(dma_dev)
#define MPSC_RXB_SIZE (MPSC_RXR_ENTRIES * MPSC_RXBE_SIZE)

#define MPSC_TXR_ENTRIES 32
-#define MPSC_TXRE_SIZE dma_get_cache_alignment()
+#define MPSC_TXRE_SIZE dma_get_cache_alignment(dma_dev)
#define MPSC_TXR_SIZE (MPSC_TXR_ENTRIES * MPSC_TXRE_SIZE)
-#define MPSC_TXBE_SIZE dma_get_cache_alignment()
+#define MPSC_TXBE_SIZE dma_get_cache_alignment(dma_dev)
#define MPSC_TXB_SIZE (MPSC_TXR_ENTRIES * MPSC_TXBE_SIZE)

#define MPSC_DMA_ALLOC_SIZE (MPSC_RXR_SIZE + MPSC_RXB_SIZE + MPSC_TXR_SIZE \
- + MPSC_TXB_SIZE + dma_get_cache_alignment() /* for alignment */)
+ + MPSC_TXB_SIZE + dma_get_cache_alignment(dma_dev) /* for alignment */)

/* Rx and Tx Ring entry descriptors -- assume entry size is <= cacheline size */
struct mpsc_rx_desc {
@@ -520,6 +520,7 @@ static uint mpsc_sdma_tx_active(struct mpsc_port_info *pi)
static void mpsc_sdma_start_tx(struct mpsc_port_info *pi)
{
struct mpsc_tx_desc *txre, *txre_p;
+ struct device *dma_dev = pi->port.dev;

/* If tx isn't running & there's a desc ready to go, start it */
if (!mpsc_sdma_tx_active(pi)) {
@@ -738,7 +739,7 @@ static void mpsc_init_hw(struct mpsc_port_info *pi)

mpsc_brg_init(pi, pi->brg_clk_src);
mpsc_brg_enable(pi);
- mpsc_sdma_init(pi, dma_get_cache_alignment()); /* burst a cacheline */
+ mpsc_sdma_init(pi, dma_get_cache_alignment(pi->port.dev)); /* burst a cacheline */
mpsc_sdma_stop(pi);
mpsc_hw_init(pi);
}
@@ -746,6 +747,7 @@ static void mpsc_init_hw(struct mpsc_port_info *pi)
static int mpsc_alloc_ring_mem(struct mpsc_port_info *pi)
{
int rc = 0;
+ struct device *dma_dev = pi->port.dev;

pr_debug("mpsc_alloc_ring_mem[%d]: Allocating ring mem\n",
pi->port.line);
@@ -769,6 +771,8 @@ static int mpsc_alloc_ring_mem(struct mpsc_port_info *pi)

static void mpsc_free_ring_mem(struct mpsc_port_info *pi)
{
+ struct device *dma_dev = pi->port.dev;
+
pr_debug("mpsc_free_ring_mem[%d]: Freeing ring mem\n", pi->port.line);

if (pi->dma_region) {
@@ -784,6 +788,7 @@ static void mpsc_init_rings(struct mpsc_port_info *pi)
{
struct mpsc_rx_desc *rxre;
struct mpsc_tx_desc *txre;
+ struct device *dma_dev = pi->port.dev;
dma_addr_t dp, dp_p;
u8 *bp, *bp_p;
int i;
@@ -798,8 +803,8 @@ static void mpsc_init_rings(struct mpsc_port_info *pi)
* Descriptors & buffers are multiples of cacheline size and must be
* cacheline aligned.
*/
- dp = ALIGN((u32)pi->dma_region, dma_get_cache_alignment());
- dp_p = ALIGN((u32)pi->dma_region_p, dma_get_cache_alignment());
+ dp = ALIGN((u32)pi->dma_region, dma_get_cache_alignment(dma_dev));
+ dp_p = ALIGN((u32)pi->dma_region_p, dma_get_cache_alignment(dma_dev));

/*
* Partition dma region into rx ring descriptor, rx buffers,
@@ -936,6 +941,7 @@ static int serial_polled;
static int mpsc_rx_intr(struct mpsc_port_info *pi, unsigned long *flags)
{
struct mpsc_rx_desc *rxre;
+ struct device *dma_dev = pi->port.dev;
struct tty_port *port = &pi->port.state->port;
u32 cmdstat, bytes_in, i;
int rc = 0;
@@ -1091,6 +1097,7 @@ static int mpsc_rx_intr(struct mpsc_port_info *pi, unsigned long *flags)
static void mpsc_setup_tx_desc(struct mpsc_port_info *pi, u32 count, u32 intr)
{
struct mpsc_tx_desc *txre;
+ struct device *dma_dev = pi->port.dev;

txre = (struct mpsc_tx_desc *)(pi->txr
+ (pi->txr_head * MPSC_TXRE_SIZE));
@@ -1113,6 +1120,7 @@ static void mpsc_setup_tx_desc(struct mpsc_port_info *pi, u32 count, u32 intr)

static void mpsc_copy_tx_data(struct mpsc_port_info *pi)
{
+ struct device *dma_dev = pi->port.dev;
struct circ_buf *xmit = &pi->port.state->xmit;
u8 *bp;
u32 i;
@@ -1166,6 +1174,7 @@ static void mpsc_copy_tx_data(struct mpsc_port_info *pi)
static int mpsc_tx_intr(struct mpsc_port_info *pi)
{
struct mpsc_tx_desc *txre;
+ struct device *dma_dev = pi->port.dev;
int rc = 0;
unsigned long iflags;

@@ -1360,6 +1369,7 @@ static int mpsc_startup(struct uart_port *port)
{
struct mpsc_port_info *pi =
container_of(port, struct mpsc_port_info, port);
+ struct device *dma_dev = pi->port.dev;
u32 flag = 0;
int rc;

@@ -1555,9 +1565,10 @@ static void mpsc_put_poll_char(struct uart_port *port,

static int mpsc_get_poll_char(struct uart_port *port)
{
+ struct mpsc_rx_desc *rxre;
struct mpsc_port_info *pi =
container_of(port, struct mpsc_port_info, port);
- struct mpsc_rx_desc *rxre;
+ struct device *dma_dev = pi->port.dev;
u32 cmdstat, bytes_in, i;
u8 *bp;

@@ -1706,6 +1717,7 @@ static const struct uart_ops mpsc_pops = {
static void mpsc_console_write(struct console *co, const char *s, uint count)
{
struct mpsc_port_info *pi = &mpsc_ports[co->index];
+ struct device *dma_dev = pi->port.dev;
u8 *bp, *dp, add_cr = 0;
int i;
unsigned long iflags;
@@ -2024,7 +2036,8 @@ static void mpsc_drv_unmap_regs(struct mpsc_port_info *pi)
static void mpsc_drv_get_platform_data(struct mpsc_port_info *pi,
struct platform_device *pd, int num)
{
- struct mpsc_pdata *pdata;
+ struct mpsc_pdata *pdata;
+ struct device *dma_dev = pi->port.dev;

pdata = dev_get_platdata(&pd->dev);

diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 8aca18c..9df918e5 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -241,7 +241,7 @@ static void enable_tx_dma(struct s3c24xx_uart_port *ourport)
/* Enable tx dma mode */
ucon = rd_regl(port, S3C2410_UCON);
ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK);
- ucon |= (dma_get_cache_alignment() >= 16) ?
+ ucon |= (dma_get_cache_alignment(port->dev) >= 16) ?
S3C64XX_UCON_TXBURST_16 : S3C64XX_UCON_TXBURST_1;
ucon |= S3C64XX_UCON_TXMODE_DMA;
wr_regl(port, S3C2410_UCON, ucon);
@@ -292,7 +292,7 @@ static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport,
if (ourport->tx_mode != S3C24XX_TX_DMA)
enable_tx_dma(ourport);

- dma->tx_size = count & ~(dma_get_cache_alignment() - 1);
+ dma->tx_size = count & ~(dma_get_cache_alignment(port->dev) - 1);
dma->tx_transfer_addr = dma->tx_addr + xmit->tail;

dma_sync_single_for_device(ourport->port.dev, dma->tx_transfer_addr,
@@ -332,7 +332,7 @@ static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)

if (!ourport->dma || !ourport->dma->tx_chan ||
count < ourport->min_dma_size ||
- xmit->tail & (dma_get_cache_alignment() - 1))
+ xmit->tail & (dma_get_cache_alignment(port->dev) - 1))
s3c24xx_serial_start_tx_pio(ourport);
else
s3c24xx_serial_start_tx_dma(ourport, count);
@@ -718,8 +718,8 @@ static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)

if (ourport->dma && ourport->dma->tx_chan &&
count >= ourport->min_dma_size) {
- int align = dma_get_cache_alignment() -
- (xmit->tail & (dma_get_cache_alignment() - 1));
+ int align = dma_get_cache_alignment(port->dev) -
+ (xmit->tail & (dma_get_cache_alignment(port->dev) - 1));
if (count-align >= ourport->min_dma_size) {
dma_count = count-align;
count = align;
@@ -870,7 +870,7 @@ static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
dma->tx_conf.direction = DMA_MEM_TO_DEV;
dma->tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
dma->tx_conf.dst_addr = p->port.mapbase + S3C2410_UTXH;
- if (dma_get_cache_alignment() >= 16)
+ if (dma_get_cache_alignment(p->port.dev) >= 16)
dma->tx_conf.dst_maxburst = 16;
else
dma->tx_conf.dst_maxburst = 1;
@@ -1849,7 +1849,7 @@ static int s3c24xx_serial_probe(struct platform_device *pdev)
* so find minimal transfer size suitable for DMA mode
*/
ourport->min_dma_size = max_t(int, ourport->port.fifosize,
- dma_get_cache_alignment());
+ dma_get_cache_alignment(ourport->port.dev));

dbg("%s: initialising port %p...\n", __func__, ourport);

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 29ce981..1326023 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -131,6 +131,7 @@ struct dma_map_ops {
#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
u64 (*get_required_mask)(struct device *dev);
#endif
+ int (*get_cache_alignment)(struct device *dev);
int is_phys;
};

@@ -697,12 +698,18 @@ static inline void *dma_zalloc_coherent(struct device *dev, size_t size,
}

#ifdef CONFIG_HAS_DMA
-static inline int dma_get_cache_alignment(void)
-{
-#ifdef ARCH_DMA_MINALIGN
- return ARCH_DMA_MINALIGN;
+
+#ifndef ARCH_DMA_MINALIGN
+#define ARCH_DMA_MINALIGN 1
#endif
- return 1;
+
+static inline int dma_get_cache_alignment(struct device *dev)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+ if (dev && ops && ops->get_cache_alignment)
+ return ops->get_cache_alignment(dev);
+
+ return ARCH_DMA_MINALIGN; /* compatible behavior */
}
#endif

--
2.7.0