[PATCH kernel v2 2/4] KVM: PPC: Add @page_shift to kvmppc_spapr_tce_table
Alexey Kardashevskiy
aik at ozlabs.ru
Tue Mar 1 17:54:38 AEDT 2016
At the moment the kvmppc_spapr_tce_table struct can only describe
4GB windows and handle fixed size (4K) pages. Dynamic DMA windows
support more so these limits need to be extended.
This replaces window_size (in bytes, 4GB max) with page_shift (32bit)
and size (64bit, in pages).
This should cause no behavioural change as this is changing
the internal structures only - the user interface still only
allows one to create a 32-bit table with 4KiB pages at this stage.
Signed-off-by: Alexey Kardashevskiy <aik at ozlabs.ru>
Reviewed-by: David Gibson <david at gibson.dropbear.id.au>
---
Changes:
v3:
* added a note that this only changes the internal structure
---
arch/powerpc/include/asm/kvm_host.h | 3 ++-
arch/powerpc/kvm/book3s_64_vio.c | 22 +++++++++++-----------
arch/powerpc/kvm/book3s_64_vio_hv.c | 21 ++++++++++-----------
3 files changed, 23 insertions(+), 23 deletions(-)
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index ffdbc2d..edf66f7 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -182,8 +182,9 @@ struct kvmppc_spapr_tce_table {
struct list_head list;
struct kvm *kvm;
u64 liobn;
- u32 window_size;
struct rcu_head rcu;
+ u32 page_shift;
+ u64 size; /* window size in pages */
struct page *pages[0];
};
diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c
index 94c8e7e..61cbc44 100644
--- a/arch/powerpc/kvm/book3s_64_vio.c
+++ b/arch/powerpc/kvm/book3s_64_vio.c
@@ -40,10 +40,9 @@
#include <asm/iommu.h>
#include <asm/tce.h>
-static unsigned long kvmppc_tce_pages(unsigned long window_size)
+static unsigned long kvmppc_tce_pages(unsigned long iommu_pages)
{
- return ALIGN((window_size >> IOMMU_PAGE_SHIFT_4K)
- * sizeof(u64), PAGE_SIZE) / PAGE_SIZE;
+ return ALIGN(iommu_pages * sizeof(u64), PAGE_SIZE) / PAGE_SIZE;
}
static unsigned long kvmppc_stt_pages(unsigned long tce_pages)
@@ -95,8 +94,7 @@ static void release_spapr_tce_table(struct rcu_head *head)
{
struct kvmppc_spapr_tce_table *stt = container_of(head,
struct kvmppc_spapr_tce_table, rcu);
- int i;
- unsigned long npages = kvmppc_tce_pages(stt->window_size);
+ unsigned long i, npages = kvmppc_tce_pages(stt->size);
for (i = 0; i < npages; i++)
__free_page(stt->pages[i]);
@@ -109,7 +107,7 @@ static int kvm_spapr_tce_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
struct kvmppc_spapr_tce_table *stt = vma->vm_file->private_data;
struct page *page;
- if (vmf->pgoff >= kvmppc_tce_pages(stt->window_size))
+ if (vmf->pgoff >= kvmppc_tce_pages(stt->size))
return VM_FAULT_SIGBUS;
page = stt->pages[vmf->pgoff];
@@ -137,7 +135,7 @@ static int kvm_spapr_tce_release(struct inode *inode, struct file *filp)
kvm_put_kvm(stt->kvm);
kvmppc_account_memlimit(
- kvmppc_stt_pages(kvmppc_tce_pages(stt->window_size)), false);
+ kvmppc_stt_pages(kvmppc_tce_pages(stt->size)), false);
call_rcu(&stt->rcu, release_spapr_tce_table);
return 0;
@@ -152,7 +150,7 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
struct kvm_create_spapr_tce *args)
{
struct kvmppc_spapr_tce_table *stt = NULL;
- unsigned long npages;
+ unsigned long npages, size;
int ret = -ENOMEM;
int i;
@@ -162,7 +160,8 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
return -EBUSY;
}
- npages = kvmppc_tce_pages(args->window_size);
+ size = args->window_size >> IOMMU_PAGE_SHIFT_4K;
+ npages = kvmppc_tce_pages(size);
ret = kvmppc_account_memlimit(kvmppc_stt_pages(npages), true);
if (ret) {
stt = NULL;
@@ -175,7 +174,8 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
goto fail;
stt->liobn = args->liobn;
- stt->window_size = args->window_size;
+ stt->page_shift = IOMMU_PAGE_SHIFT_4K;
+ stt->size = size;
stt->kvm = kvm;
for (i = 0; i < npages; i++) {
@@ -218,7 +218,7 @@ long kvmppc_h_put_tce_indirect(struct kvm_vcpu *vcpu,
if (!stt)
return H_TOO_HARD;
- entry = ioba >> IOMMU_PAGE_SHIFT_4K;
+ entry = ioba >> stt->page_shift;
/*
* SPAPR spec says that the maximum size of the list is 512 TCEs
* so the whole table fits in 4K page
diff --git a/arch/powerpc/kvm/book3s_64_vio_hv.c b/arch/powerpc/kvm/book3s_64_vio_hv.c
index 0486aa2..c786a58 100644
--- a/arch/powerpc/kvm/book3s_64_vio_hv.c
+++ b/arch/powerpc/kvm/book3s_64_vio_hv.c
@@ -72,11 +72,10 @@ EXPORT_SYMBOL_GPL(kvmppc_find_table);
long kvmppc_ioba_validate(struct kvmppc_spapr_tce_table *stt,
unsigned long ioba, unsigned long npages)
{
- unsigned long mask = (1ULL << IOMMU_PAGE_SHIFT_4K) - 1;
- unsigned long idx = ioba >> IOMMU_PAGE_SHIFT_4K;
- unsigned long size = stt->window_size >> IOMMU_PAGE_SHIFT_4K;
+ unsigned long mask = (1ULL << stt->page_shift) - 1;
+ unsigned long idx = ioba >> stt->page_shift;
- if ((ioba & mask) || (idx + npages > size) || (idx + npages < idx))
+ if ((ioba & mask) || (idx + npages > stt->size) || (idx + npages < idx))
return H_PARAMETER;
return H_SUCCESS;
@@ -96,8 +95,8 @@ EXPORT_SYMBOL_GPL(kvmppc_ioba_validate);
*/
long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt, unsigned long tce)
{
- unsigned long mask =
- ~(IOMMU_PAGE_MASK_4K | TCE_PCI_WRITE | TCE_PCI_READ);
+ unsigned long page_mask = ~((1ULL << stt->page_shift) - 1);
+ unsigned long mask = ~(page_mask | TCE_PCI_WRITE | TCE_PCI_READ);
if (tce & mask)
return H_PARAMETER;
@@ -198,7 +197,7 @@ long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
if (ret != H_SUCCESS)
return ret;
- kvmppc_tce_put(stt, ioba >> IOMMU_PAGE_SHIFT_4K, tce);
+ kvmppc_tce_put(stt, ioba >> stt->page_shift, tce);
return H_SUCCESS;
}
@@ -244,7 +243,7 @@ long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu,
if (!stt)
return H_TOO_HARD;
- entry = ioba >> IOMMU_PAGE_SHIFT_4K;
+ entry = ioba >> stt->page_shift;
/*
* The spec says that the maximum size of the list is 512 TCEs
* so the whole table addressed resides in 4K page
@@ -313,8 +312,8 @@ long kvmppc_h_stuff_tce(struct kvm_vcpu *vcpu,
if (tce_value & (TCE_PCI_WRITE | TCE_PCI_READ))
return H_PARAMETER;
- for (i = 0; i < npages; ++i, ioba += IOMMU_PAGE_SIZE_4K)
- kvmppc_tce_put(stt, ioba >> IOMMU_PAGE_SHIFT_4K, tce_value);
+ for (i = 0; i < npages; ++i, ioba += (1ULL << stt->page_shift))
+ kvmppc_tce_put(stt, ioba >> stt->page_shift, tce_value);
return H_SUCCESS;
}
@@ -336,7 +335,7 @@ long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
if (ret != H_SUCCESS)
return ret;
- idx = ioba >> IOMMU_PAGE_SHIFT_4K;
+ idx = ioba >> stt->page_shift;
page = stt->pages[idx / TCES_PER_PAGE];
tbl = (u64 *)page_address(page);
--
2.5.0.rc3
More information about the Linuxppc-dev
mailing list