summaryrefslogtreecommitdiff
path: root/kernel/dma
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/dma')
-rw-r--r--kernel/dma/coherent.c12
-rw-r--r--kernel/dma/contiguous.c3
-rw-r--r--kernel/dma/direct.c44
-rw-r--r--kernel/dma/mapping.c43
4 files changed, 67 insertions, 35 deletions
diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c
index 3b2bdca9f1d4..77c8d9487a9a 100644
--- a/kernel/dma/coherent.c
+++ b/kernel/dma/coherent.c
@@ -336,16 +336,22 @@ static phys_addr_t dma_reserved_default_memory_size __initdata;
static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev)
{
- if (!rmem->priv) {
- struct dma_coherent_mem *mem;
+ struct dma_coherent_mem *mem = rmem->priv;
+ if (!mem) {
mem = dma_init_coherent_memory(rmem->base, rmem->base,
rmem->size, true);
if (IS_ERR(mem))
return PTR_ERR(mem);
rmem->priv = mem;
}
- dma_assign_coherent_memory(dev, rmem->priv);
+
+ /* Warn if the device potentially can't use the reserved memory */
+ if (mem->device_base + rmem->size - 1 >
+ min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit))
+ dev_warn(dev, "reserved memory is beyond device's set DMA address range\n");
+
+ dma_assign_coherent_memory(dev, mem);
return 0;
}
diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
index 055da410ac71..8df0dfaaca18 100644
--- a/kernel/dma/contiguous.c
+++ b/kernel/dma/contiguous.c
@@ -64,8 +64,7 @@ struct cma *dma_contiguous_default_area;
* Users, who want to set the size of global CMA area for their system
* should use cma= kernel parameter.
*/
-static const phys_addr_t size_bytes __initconst =
- (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M;
+#define size_bytes ((phys_addr_t)CMA_SIZE_MBYTES * SZ_1M)
static phys_addr_t size_cmdline __initdata = -1;
static phys_addr_t base_cmdline __initdata;
static phys_addr_t limit_cmdline __initdata;
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index b8fe0b3d0ffb..24c359d9c879 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -13,6 +13,7 @@
#include <linux/vmalloc.h>
#include <linux/set_memory.h>
#include <linux/slab.h>
+#include <linux/pci-p2pdma.h>
#include "direct.h"
/*
@@ -462,34 +463,33 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
enum dma_data_direction dir, unsigned long attrs)
{
struct pci_p2pdma_map_state p2pdma_state = {};
- enum pci_p2pdma_map_type map;
struct scatterlist *sg;
int i, ret;
for_each_sg(sgl, sg, nents, i) {
- if (is_pci_p2pdma_page(sg_page(sg))) {
- map = pci_p2pdma_map_segment(&p2pdma_state, dev, sg);
- switch (map) {
- case PCI_P2PDMA_MAP_BUS_ADDR:
- continue;
- case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE:
- /*
- * Any P2P mapping that traverses the PCI
- * host bridge must be mapped with CPU physical
- * address and not PCI bus addresses. This is
- * done with dma_direct_map_page() below.
- */
- break;
- default:
- ret = -EREMOTEIO;
+ switch (pci_p2pdma_state(&p2pdma_state, dev, sg_page(sg))) {
+ case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE:
+ /*
+ * Any P2P mapping that traverses the PCI host bridge
+ * must be mapped with CPU physical address and not PCI
+ * bus addresses.
+ */
+ break;
+ case PCI_P2PDMA_MAP_NONE:
+ sg->dma_address = dma_direct_map_page(dev, sg_page(sg),
+ sg->offset, sg->length, dir, attrs);
+ if (sg->dma_address == DMA_MAPPING_ERROR) {
+ ret = -EIO;
goto out_unmap;
}
- }
-
- sg->dma_address = dma_direct_map_page(dev, sg_page(sg),
- sg->offset, sg->length, dir, attrs);
- if (sg->dma_address == DMA_MAPPING_ERROR) {
- ret = -EIO;
+ break;
+ case PCI_P2PDMA_MAP_BUS_ADDR:
+ sg->dma_address = pci_p2pdma_bus_addr_map(&p2pdma_state,
+ sg_phys(sg));
+ sg_dma_mark_bus_address(sg);
+ continue;
+ default:
+ ret = -EREMOTEIO;
goto out_unmap;
}
sg_dma_len(sg) = sg->length;
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index cda127027e48..107e4a4d251d 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -443,6 +443,24 @@ bool __dma_need_sync(struct device *dev, dma_addr_t dma_addr)
}
EXPORT_SYMBOL_GPL(__dma_need_sync);
+/**
+ * dma_need_unmap - does this device need dma_unmap_* operations
+ * @dev: device to check
+ *
+ * If this function returns %false, drivers can skip calling dma_unmap_* after
+ * finishing an I/O. This function must be called after all mappings that might
+ * need to be unmapped have been performed.
+ */
+bool dma_need_unmap(struct device *dev)
+{
+ if (!dma_map_direct(dev, get_dma_ops(dev)))
+ return true;
+ if (!dev->dma_skip_sync)
+ return true;
+ return IS_ENABLED(CONFIG_DMA_API_DEBUG);
+}
+EXPORT_SYMBOL_GPL(dma_need_unmap);
+
static void dma_setup_need_sync(struct device *dev)
{
const struct dma_map_ops *ops = get_dma_ops(dev);
@@ -910,6 +928,19 @@ int dma_set_coherent_mask(struct device *dev, u64 mask)
}
EXPORT_SYMBOL(dma_set_coherent_mask);
+static bool __dma_addressing_limited(struct device *dev)
+{
+ const struct dma_map_ops *ops = get_dma_ops(dev);
+
+ if (min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
+ dma_get_required_mask(dev))
+ return true;
+
+ if (unlikely(ops) || use_dma_iommu(dev))
+ return false;
+ return !dma_direct_all_ram_mapped(dev);
+}
+
/**
* dma_addressing_limited - return if the device is addressing limited
* @dev: device to check
@@ -920,15 +951,11 @@ EXPORT_SYMBOL(dma_set_coherent_mask);
*/
bool dma_addressing_limited(struct device *dev)
{
- const struct dma_map_ops *ops = get_dma_ops(dev);
-
- if (min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
- dma_get_required_mask(dev))
- return true;
-
- if (unlikely(ops) || use_dma_iommu(dev))
+ if (!__dma_addressing_limited(dev))
return false;
- return !dma_direct_all_ram_mapped(dev);
+
+ dev_dbg(dev, "device is DMA addressing limited\n");
+ return true;
}
EXPORT_SYMBOL_GPL(dma_addressing_limited);