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-rw-r--r--Documentation/DMA-attributes.txt10
-rw-r--r--arch/arm/mm/dma-mapping.c60
-rw-r--r--arch/arm64/mm/dma-mapping.c6
-rw-r--r--drivers/dma/pl330.c5
-rw-r--r--drivers/iommu/arm-smmu-v3.c7
-rw-r--r--drivers/iommu/arm-smmu.c2
-rw-r--r--drivers/iommu/dma-iommu.c12
-rw-r--r--drivers/iommu/io-pgtable-arm-v7s.c6
-rw-r--r--drivers/iommu/io-pgtable-arm.c5
-rw-r--r--include/linux/dma-iommu.h3
-rw-r--r--include/linux/dma-mapping.h7
-rw-r--r--include/linux/iommu.h7
12 files changed, 82 insertions, 48 deletions
diff --git a/Documentation/DMA-attributes.txt b/Documentation/DMA-attributes.txt
index 98bf7ac29aad..44c6bc496eee 100644
--- a/Documentation/DMA-attributes.txt
+++ b/Documentation/DMA-attributes.txt
@@ -143,3 +143,13 @@ So, this provides a way for drivers to avoid those error messages on calls
where allocation failures are not a problem, and shouldn't bother the logs.
NOTE: At the moment DMA_ATTR_NO_WARN is only implemented on PowerPC.
+
+DMA_ATTR_PRIVILEGED
+------------------------------
+
+Some advanced peripherals such as remote processors and GPUs perform
+accesses to DMA buffers in both privileged "supervisor" and unprivileged
+"user" modes. This attribute is used to indicate to the DMA-mapping
+subsystem that the buffer is fully accessible at the elevated privilege
+level (and ideally inaccessible or at least read-only at the
+lesser-privileged levels).
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index ab7710002ba6..82d3e79ec82b 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1171,6 +1171,25 @@ core_initcall(dma_debug_do_init);
#ifdef CONFIG_ARM_DMA_USE_IOMMU
+static int __dma_info_to_prot(enum dma_data_direction dir, unsigned long attrs)
+{
+ int prot = 0;
+
+ if (attrs & DMA_ATTR_PRIVILEGED)
+ prot |= IOMMU_PRIV;
+
+ switch (dir) {
+ case DMA_BIDIRECTIONAL:
+ return prot | IOMMU_READ | IOMMU_WRITE;
+ case DMA_TO_DEVICE:
+ return prot | IOMMU_READ;
+ case DMA_FROM_DEVICE:
+ return prot | IOMMU_WRITE;
+ default:
+ return prot;
+ }
+}
+
/* IOMMU */
static int extend_iommu_mapping(struct dma_iommu_mapping *mapping);
@@ -1394,7 +1413,8 @@ __iommu_alloc_remap(struct page **pages, size_t size, gfp_t gfp, pgprot_t prot,
* Create a mapping in device IO address space for specified pages
*/
static dma_addr_t
-__iommu_create_mapping(struct device *dev, struct page **pages, size_t size)
+__iommu_create_mapping(struct device *dev, struct page **pages, size_t size,
+ unsigned long attrs)
{
struct dma_iommu_mapping *mapping = to_dma_iommu_mapping(dev);
unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
@@ -1419,7 +1439,7 @@ __iommu_create_mapping(struct device *dev, struct page **pages, size_t size)
len = (j - i) << PAGE_SHIFT;
ret = iommu_map(mapping->domain, iova, phys, len,
- IOMMU_READ|IOMMU_WRITE);
+ __dma_info_to_prot(DMA_BIDIRECTIONAL, attrs));
if (ret < 0)
goto fail;
iova += len;
@@ -1476,7 +1496,8 @@ static struct page **__iommu_get_pages(void *cpu_addr, unsigned long attrs)
}
static void *__iommu_alloc_simple(struct device *dev, size_t size, gfp_t gfp,
- dma_addr_t *handle, int coherent_flag)
+ dma_addr_t *handle, int coherent_flag,
+ unsigned long attrs)
{
struct page *page;
void *addr;
@@ -1488,7 +1509,7 @@ static void *__iommu_alloc_simple(struct device *dev, size_t size, gfp_t gfp,
if (!addr)
return NULL;
- *handle = __iommu_create_mapping(dev, &page, size);
+ *handle = __iommu_create_mapping(dev, &page, size, attrs);
if (*handle == DMA_ERROR_CODE)
goto err_mapping;
@@ -1522,7 +1543,7 @@ static void *__arm_iommu_alloc_attrs(struct device *dev, size_t size,
if (coherent_flag == COHERENT || !gfpflags_allow_blocking(gfp))
return __iommu_alloc_simple(dev, size, gfp, handle,
- coherent_flag);
+ coherent_flag, attrs);
/*
* Following is a work-around (a.k.a. hack) to prevent pages
@@ -1537,7 +1558,7 @@ static void *__arm_iommu_alloc_attrs(struct device *dev, size_t size,
if (!pages)
return NULL;
- *handle = __iommu_create_mapping(dev, pages, size);
+ *handle = __iommu_create_mapping(dev, pages, size, attrs);
if (*handle == DMA_ERROR_CODE)
goto err_buffer;
@@ -1672,27 +1693,6 @@ static int arm_iommu_get_sgtable(struct device *dev, struct sg_table *sgt,
GFP_KERNEL);
}
-static int __dma_direction_to_prot(enum dma_data_direction dir)
-{
- int prot;
-
- switch (dir) {
- case DMA_BIDIRECTIONAL:
- prot = IOMMU_READ | IOMMU_WRITE;
- break;
- case DMA_TO_DEVICE:
- prot = IOMMU_READ;
- break;
- case DMA_FROM_DEVICE:
- prot = IOMMU_WRITE;
- break;
- default:
- prot = 0;
- }
-
- return prot;
-}
-
/*
* Map a part of the scatter-gather list into contiguous io address space
*/
@@ -1722,7 +1722,7 @@ static int __map_sg_chunk(struct device *dev, struct scatterlist *sg,
if (!is_coherent && (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
__dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);
- prot = __dma_direction_to_prot(dir);
+ prot = __dma_info_to_prot(dir, attrs);
ret = iommu_map(mapping->domain, iova, phys, len, prot);
if (ret < 0)
@@ -1930,7 +1930,7 @@ static dma_addr_t arm_coherent_iommu_map_page(struct device *dev, struct page *p
if (dma_addr == DMA_ERROR_CODE)
return dma_addr;
- prot = __dma_direction_to_prot(dir);
+ prot = __dma_info_to_prot(dir, attrs);
ret = iommu_map(mapping->domain, dma_addr, page_to_phys(page), len, prot);
if (ret < 0)
@@ -2036,7 +2036,7 @@ static dma_addr_t arm_iommu_map_resource(struct device *dev,
if (dma_addr == DMA_ERROR_CODE)
return dma_addr;
- prot = __dma_direction_to_prot(dir) | IOMMU_MMIO;
+ prot = __dma_info_to_prot(dir, attrs) | IOMMU_MMIO;
ret = iommu_map(mapping->domain, dma_addr, addr, len, prot);
if (ret < 0)
diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index e04082700bb1..ae9f817eadf2 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -558,7 +558,7 @@ static void *__iommu_alloc_attrs(struct device *dev, size_t size,
unsigned long attrs)
{
bool coherent = is_device_dma_coherent(dev);
- int ioprot = dma_direction_to_prot(DMA_BIDIRECTIONAL, coherent);
+ int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs);
size_t iosize = size;
void *addr;
@@ -712,7 +712,7 @@ static dma_addr_t __iommu_map_page(struct device *dev, struct page *page,
unsigned long attrs)
{
bool coherent = is_device_dma_coherent(dev);
- int prot = dma_direction_to_prot(dir, coherent);
+ int prot = dma_info_to_prot(dir, coherent, attrs);
dma_addr_t dev_addr = iommu_dma_map_page(dev, page, offset, size, prot);
if (!iommu_dma_mapping_error(dev, dev_addr) &&
@@ -770,7 +770,7 @@ static int __iommu_map_sg_attrs(struct device *dev, struct scatterlist *sgl,
__iommu_sync_sg_for_device(dev, sgl, nelems, dir);
return iommu_dma_map_sg(dev, sgl, nelems,
- dma_direction_to_prot(dir, coherent));
+ dma_info_to_prot(dir, coherent, attrs));
}
static void __iommu_unmap_sg_attrs(struct device *dev,
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 740bbb942594..48720800c438 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -1867,9 +1867,10 @@ static int dmac_alloc_resources(struct pl330_dmac *pl330)
* Alloc MicroCode buffer for 'chans' Channel threads.
* A channel's buffer offset is (Channel_Id * MCODE_BUFF_PERCHAN)
*/
- pl330->mcode_cpu = dma_alloc_coherent(pl330->ddma.dev,
+ pl330->mcode_cpu = dma_alloc_attrs(pl330->ddma.dev,
chans * pl330->mcbufsz,
- &pl330->mcode_bus, GFP_KERNEL);
+ &pl330->mcode_bus, GFP_KERNEL,
+ DMA_ATTR_PRIVILEGED);
if (!pl330->mcode_cpu) {
dev_err(pl330->ddma.dev, "%s:%d Can't allocate memory!\n",
__func__, __LINE__);
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index d9cf6cb8c6cc..6cdd501a7df9 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -269,9 +269,6 @@
#define STRTAB_STE_1_SHCFG_INCOMING 1UL
#define STRTAB_STE_1_SHCFG_SHIFT 44
-#define STRTAB_STE_1_PRIVCFG_UNPRIV 2UL
-#define STRTAB_STE_1_PRIVCFG_SHIFT 48
-
#define STRTAB_STE_2_S2VMID_SHIFT 0
#define STRTAB_STE_2_S2VMID_MASK 0xffffUL
#define STRTAB_STE_2_VTCR_SHIFT 32
@@ -1076,9 +1073,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_device *smmu, u32 sid,
#ifdef CONFIG_PCI_ATS
STRTAB_STE_1_EATS_TRANS << STRTAB_STE_1_EATS_SHIFT |
#endif
- STRTAB_STE_1_STRW_NSEL1 << STRTAB_STE_1_STRW_SHIFT |
- STRTAB_STE_1_PRIVCFG_UNPRIV <<
- STRTAB_STE_1_PRIVCFG_SHIFT);
+ STRTAB_STE_1_STRW_NSEL1 << STRTAB_STE_1_STRW_SHIFT);
if (smmu->features & ARM_SMMU_FEAT_STALLS)
dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD);
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 13d26009b8e0..54368f557bed 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1217,7 +1217,7 @@ static int arm_smmu_domain_add_master(struct arm_smmu_domain *smmu_domain,
continue;
s2cr[idx].type = type;
- s2cr[idx].privcfg = S2CR_PRIVCFG_UNPRIV;
+ s2cr[idx].privcfg = S2CR_PRIVCFG_DEFAULT;
s2cr[idx].cbndx = cbndx;
arm_smmu_write_s2cr(smmu, idx);
}
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index de41ead6542a..7195d46f8233 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -245,16 +245,22 @@ int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
EXPORT_SYMBOL(iommu_dma_init_domain);
/**
- * dma_direction_to_prot - Translate DMA API directions to IOMMU API page flags
+ * dma_info_to_prot - Translate DMA API directions and attributes to IOMMU API
+ * page flags.
* @dir: Direction of DMA transfer
* @coherent: Is the DMA master cache-coherent?
+ * @attrs: DMA attributes for the mapping
*
* Return: corresponding IOMMU API page protection flags
*/
-int dma_direction_to_prot(enum dma_data_direction dir, bool coherent)
+int dma_info_to_prot(enum dma_data_direction dir, bool coherent,
+ unsigned long attrs)
{
int prot = coherent ? IOMMU_CACHE : 0;
+ if (attrs & DMA_ATTR_PRIVILEGED)
+ prot |= IOMMU_PRIV;
+
switch (dir) {
case DMA_BIDIRECTIONAL:
return prot | IOMMU_READ | IOMMU_WRITE;
@@ -697,7 +703,7 @@ dma_addr_t iommu_dma_map_resource(struct device *dev, phys_addr_t phys,
size_t size, enum dma_data_direction dir, unsigned long attrs)
{
return __iommu_dma_map(dev, phys, size,
- dma_direction_to_prot(dir, false) | IOMMU_MMIO);
+ dma_info_to_prot(dir, false, attrs) | IOMMU_MMIO);
}
void iommu_dma_unmap_resource(struct device *dev, dma_addr_t handle,
diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c
index 0769276c0537..1c049e2e12bf 100644
--- a/drivers/iommu/io-pgtable-arm-v7s.c
+++ b/drivers/iommu/io-pgtable-arm-v7s.c
@@ -265,7 +265,9 @@ static arm_v7s_iopte arm_v7s_prot_to_pte(int prot, int lvl,
if (!(prot & IOMMU_MMIO))
pte |= ARM_V7S_ATTR_TEX(1);
if (ap) {
- pte |= ARM_V7S_PTE_AF | ARM_V7S_PTE_AP_UNPRIV;
+ pte |= ARM_V7S_PTE_AF;
+ if (!(prot & IOMMU_PRIV))
+ pte |= ARM_V7S_PTE_AP_UNPRIV;
if (!(prot & IOMMU_WRITE))
pte |= ARM_V7S_PTE_AP_RDONLY;
}
@@ -288,6 +290,8 @@ static int arm_v7s_pte_to_prot(arm_v7s_iopte pte, int lvl)
if (!(attr & ARM_V7S_PTE_AP_RDONLY))
prot |= IOMMU_WRITE;
+ if (!(attr & ARM_V7S_PTE_AP_UNPRIV))
+ prot |= IOMMU_PRIV;
if ((attr & (ARM_V7S_TEX_MASK << ARM_V7S_TEX_SHIFT)) == 0)
prot |= IOMMU_MMIO;
else if (pte & ARM_V7S_ATTR_C)
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index a40ce3406fef..feacc54bec68 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -350,11 +350,14 @@ static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data,
if (data->iop.fmt == ARM_64_LPAE_S1 ||
data->iop.fmt == ARM_32_LPAE_S1) {
- pte = ARM_LPAE_PTE_AP_UNPRIV | ARM_LPAE_PTE_nG;
+ pte = ARM_LPAE_PTE_nG;
if (!(prot & IOMMU_WRITE) && (prot & IOMMU_READ))
pte |= ARM_LPAE_PTE_AP_RDONLY;
+ if (!(prot & IOMMU_PRIV))
+ pte |= ARM_LPAE_PTE_AP_UNPRIV;
+
if (prot & IOMMU_MMIO)
pte |= (ARM_LPAE_MAIR_ATTR_IDX_DEV
<< ARM_LPAE_PTE_ATTRINDX_SHIFT);
diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h
index 28df844a23b6..3a846f9ec0fd 100644
--- a/include/linux/dma-iommu.h
+++ b/include/linux/dma-iommu.h
@@ -35,7 +35,8 @@ int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base,
u64 size, struct device *dev);
/* General helpers for DMA-API <-> IOMMU-API interaction */
-int dma_direction_to_prot(enum dma_data_direction dir, bool coherent);
+int dma_info_to_prot(enum dma_data_direction dir, bool coherent,
+ unsigned long attrs);
/*
* These implement the bulk of the relevant DMA mapping callbacks, but require
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 10c5a17b1f51..c24721a33b4c 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -63,6 +63,13 @@
#define DMA_ATTR_NO_WARN (1UL << 8)
/*
+ * DMA_ATTR_PRIVILEGED: used to indicate that the buffer is fully
+ * accessible at an elevated privilege level (and ideally inaccessible or
+ * at least read-only at lesser-privileged levels).
+ */
+#define DMA_ATTR_PRIVILEGED (1UL << 9)
+
+/*
* A dma_addr_t can hold any valid DMA or bus address for the platform.
* It can be given to a device to use as a DMA source or target. A CPU cannot
* reference a dma_addr_t directly because there may be translation between
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index bec3730dc009..add30c375332 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -31,6 +31,13 @@
#define IOMMU_CACHE (1 << 2) /* DMA cache coherency */
#define IOMMU_NOEXEC (1 << 3)
#define IOMMU_MMIO (1 << 4) /* e.g. things like MSI doorbells */
+/*
+ * This is to make the IOMMU API setup privileged
+ * mapppings accessible by the master only at higher
+ * privileged execution level and inaccessible at
+ * less privileged levels.
+ */
+#define IOMMU_PRIV (1 << 5)
struct iommu_ops;
struct iommu_group;