* Joerg Roedel ([email protected]) wrote:
> On Fri, Jun 22, 2012 at 03:28:14PM +0400, Alexandra N. Kossovsky wrote:
> > Hello.
> >
> > It is not clear from the documentation if iommu_map()/iommu_unmap()
> > functions may be called from atomic context.
> > In case of Intel IOMMU, it works; in case of AMD IOMMU, it does not.
> >
> > Was it done by purpose? May I propose a patch for AMD IOMMU replacing
> > GFP_KERNEL by GFP_ATOMIC to make things better?
>
> Well, a better option would be to have an iommu_map_atomic() alongside
> the current iommu_map API call.
A simple change for ->map to include flags and an iommu_map_atomic helper
that calls ->map w/ GFP_ATOMIC will hit this in AMD IOMMU:
mutex_lock(&domain->api_lock);
- ret = iommu_map_page(domain, iova, paddr, prot, page_size);
+ ret = iommu_map_page(domain, iova, paddr, prot, page_size, flags);
mutex_unlock(&domain->api_lock);
thanks,
-chris
---
From: Chris Wright <[email protected]>
Subject: [PATCH example] iommu: add gfp flags to ->map
untested, not to apply
---
drivers/iommu/amd_iommu.c | 12 +++++++-----
drivers/iommu/intel-iommu.c | 2 +-
drivers/iommu/iommu.c | 19 ++++++++++++++++---
drivers/iommu/msm_iommu.c | 2 +-
drivers/iommu/omap-iommu.c | 16 +++++++++-------
drivers/iommu/tegra-gart.c | 2 +-
drivers/iommu/tegra-smmu.c | 2 +-
include/linux/iommu.h | 11 ++++++++++-
8 files changed, 46 insertions(+), 20 deletions(-)
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index a5bee8e..9160810 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -1186,7 +1186,8 @@ static int iommu_map_page(struct protection_domain *dom,
unsigned long bus_addr,
unsigned long phys_addr,
int prot,
- unsigned long page_size)
+ unsigned long page_size,
+ gfp_t flags)
{
u64 __pte, *pte;
int i, count;
@@ -1197,7 +1198,7 @@ static int iommu_map_page(struct protection_domain *dom,
bus_addr = PAGE_ALIGN(bus_addr);
phys_addr = PAGE_ALIGN(phys_addr);
count = PAGE_SIZE_PTE_COUNT(page_size);
- pte = alloc_pte(dom, bus_addr, page_size, NULL, GFP_KERNEL);
+ pte = alloc_pte(dom, bus_addr, page_size, NULL, flags);
for (i = 0; i < count; ++i)
if (IOMMU_PTE_PRESENT(pte[i]))
@@ -1297,7 +1298,7 @@ static int dma_ops_unity_map(struct dma_ops_domain
*dma_dom,
for (addr = e->address_start; addr < e->address_end;
addr += PAGE_SIZE) {
ret = iommu_map_page(&dma_dom->domain, addr, addr, e->prot,
- PAGE_SIZE);
+ PAGE_SIZE, GFP_KERNEL);
if (ret)
return ret;
/*
@@ -3116,7 +3117,8 @@ static int amd_iommu_attach_device(struct iommu_domain
*dom,
}
static int amd_iommu_map(struct iommu_domain *dom, unsigned long iova,
- phys_addr_t paddr, size_t page_size, int iommu_prot)
+ phys_addr_t paddr, size_t page_size, int iommu_prot,
+ gfp_t flags)
{
struct protection_domain *domain = dom->priv;
int prot = 0;
@@ -3131,7 +3133,7 @@ static int amd_iommu_map(struct iommu_domain *dom,
unsigned long iova,
prot |= IOMMU_PROT_IW;
mutex_lock(&domain->api_lock);
- ret = iommu_map_page(domain, iova, paddr, prot, page_size);
+ ret = iommu_map_page(domain, iova, paddr, prot, page_size, flags);
mutex_unlock(&domain->api_lock);
return ret;
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index bf2fbaa..19fa562 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -4010,7 +4010,7 @@ static void intel_iommu_detach_device(struct iommu_domain
*domain,
static int intel_iommu_map(struct iommu_domain *domain,
unsigned long iova, phys_addr_t hpa,
- size_t size, int iommu_prot)
+ size_t size, int iommu_prot, gfp_t flags)
{
struct dmar_domain *dmar_domain = domain->priv;
u64 max_addr;
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 2198b2d..13e8dcd 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -209,8 +209,8 @@ int iommu_domain_has_cap(struct iommu_domain *domain,
}
EXPORT_SYMBOL_GPL(iommu_domain_has_cap);
-int iommu_map(struct iommu_domain *domain, unsigned long iova,
- phys_addr_t paddr, size_t size, int prot)
+static int __iommu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot, gfp_t flags)
{
unsigned long orig_iova = iova;
unsigned int min_pagesz;
@@ -269,7 +269,7 @@ int iommu_map(struct iommu_domain *domain, unsigned long
iova,
pr_debug("mapping: iova 0x%lx pa 0x%lx pgsize %lu\n", iova,
(unsigned long)paddr, pgsize);
- ret = domain->ops->map(domain, iova, paddr, pgsize, prot);
+ ret = domain->ops->map(domain, iova, paddr, pgsize, prot,
flags);
if (ret)
break;
@@ -284,8 +284,21 @@ int iommu_map(struct iommu_domain *domain, unsigned long
iova,
return ret;
}
+
+int iommu_map(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot)
+{
+ return __iommu_map(domain, iova, paddr, size, prot, GFP_KERNEL);
+}
EXPORT_SYMBOL_GPL(iommu_map);
+int iommu_map_atomic(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot)
+{
+ return __iommu_map(domain, iova, paddr, size, prot, GFP_ATOMIC);
+}
+EXPORT_SYMBOL_GPL(iommu_map_atomic);
+
size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t
size)
{
size_t unmapped_page, unmapped = 0;
diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
index cee307e..7381418 100644
--- a/drivers/iommu/msm_iommu.c
+++ b/drivers/iommu/msm_iommu.c
@@ -355,7 +355,7 @@ fail:
}
static int msm_iommu_map(struct iommu_domain *domain, unsigned long va,
- phys_addr_t pa, size_t len, int prot)
+ phys_addr_t pa, size_t len, int prot, gfp_t flags)
{
struct msm_priv *priv;
unsigned long flags;
diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index 6899dcd..e20cde4 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -493,7 +493,7 @@ static void iopte_free(u32 *iopte)
kmem_cache_free(iopte_cachep, iopte);
}
-static u32 *iopte_alloc(struct omap_iommu *obj, u32 *iopgd, u32 da)
+static u32 *iopte_alloc(struct omap_iommu *obj, u32 *iopgd, u32 da, gfp_t gfp)
{
u32 *iopte;
@@ -505,7 +505,7 @@ static u32 *iopte_alloc(struct omap_iommu *obj, u32 *iopgd,
u32 da)
* do the allocation outside the page table lock
*/
spin_unlock(&obj->page_table_lock);
- iopte = kmem_cache_zalloc(iopte_cachep, GFP_KERNEL);
+ iopte = kmem_cache_zalloc(iopte_cachep, gfp);
spin_lock(&obj->page_table_lock);
if (!*iopgd) {
@@ -563,10 +563,11 @@ static int iopgd_alloc_super(struct omap_iommu *obj, u32
da, u32 pa, u32 prot)
return 0;
}
-static int iopte_alloc_page(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
+static int iopte_alloc_page(struct omap_iommu *obj, u32 da, u32 pa, u32 prot,
+ gfp_t gfp)
{
u32 *iopgd = iopgd_offset(obj, da);
- u32 *iopte = iopte_alloc(obj, iopgd, da);
+ u32 *iopte = iopte_alloc(obj, iopgd, da, gfp);
if (IS_ERR(iopte))
return PTR_ERR(iopte);
@@ -580,10 +581,11 @@ static int iopte_alloc_page(struct omap_iommu *obj, u32
da, u32 pa, u32 prot)
return 0;
}
-static int iopte_alloc_large(struct omap_iommu *obj, u32 da, u32 pa, u32 prot)
+static int iopte_alloc_large(struct omap_iommu *obj, u32 da, u32 pa, u32 prot,
+ gfp_t gfp)
{
u32 *iopgd = iopgd_offset(obj, da);
- u32 *iopte = iopte_alloc(obj, iopgd, da);
+ u32 *iopte = iopte_alloc(obj, iopgd, da, gfp);
int i;
if ((da | pa) & ~IOLARGE_MASK) {
@@ -1014,7 +1016,7 @@ static void iopte_cachep_ctor(void *iopte)
}
static int omap_iommu_map(struct iommu_domain *domain, unsigned long da,
- phys_addr_t pa, size_t bytes, int prot)
+ phys_addr_t pa, size_t bytes, int prot, gfp_t gfp)
{
struct omap_iommu_domain *omap_domain = domain->priv;
struct omap_iommu *oiommu = omap_domain->iommu_dev;
diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c
index 779306e..b8e8889 100644
--- a/drivers/iommu/tegra-gart.c
+++ b/drivers/iommu/tegra-gart.c
@@ -233,7 +233,7 @@ static void gart_iommu_domain_destroy(struct iommu_domain
*domain)
}
static int gart_iommu_map(struct iommu_domain *domain, unsigned long iova,
- phys_addr_t pa, size_t bytes, int prot)
+ phys_addr_t pa, size_t bytes, int prot, gfp_t gfp)
{
struct gart_device *gart = domain->priv;
unsigned long flags;
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index eb93c82..ab71e81 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -627,7 +627,7 @@ static void __smmu_iommu_map_pfn(struct smmu_as *as,
dma_addr_t iova,
}
static int smmu_iommu_map(struct iommu_domain *domain, unsigned long iova,
- phys_addr_t pa, size_t bytes, int prot)
+ phys_addr_t pa, size_t bytes, int prot, gfp_t gfp)
{
struct smmu_as *as = domain->priv;
unsigned long pfn = __phys_to_pfn(pa);
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index d937580..e9a5997 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -67,7 +67,7 @@ struct iommu_ops {
int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
int (*map)(struct iommu_domain *domain, unsigned long iova,
- phys_addr_t paddr, size_t size, int prot);
+ phys_addr_t paddr, size_t size, int prot, gfp_t flags);
size_t (*unmap)(struct iommu_domain *domain, unsigned long iova,
size_t size);
phys_addr_t (*iova_to_phys)(struct iommu_domain *domain,
@@ -88,6 +88,8 @@ extern void iommu_detach_device(struct iommu_domain *domain,
struct device *dev);
extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, int prot);
+extern int iommu_map_atomic(struct iommu_domain *domain, unsigned long iova,
+ phys_addr_t paddr, size_t size, int prot);
extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova,
size_t size);
extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain,
@@ -172,6 +174,13 @@ static inline int iommu_map(struct iommu_domain *domain,
unsigned long iova,
return -ENODEV;
}
+static inline int iommu_map_atomic(struct iommu_domain *domain,
+ unsigned long iova, phys_addr_t paddr,
+ int gfp_order, int prot)
+{
+ return -ENODEV;
+}
+
static inline int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
int gfp_order)
{
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