summaryrefslogtreecommitdiff
path: root/arch
diff options
context:
space:
mode:
Diffstat (limited to 'arch')
-rw-r--r--arch/arm64/include/asm/kvm_mmu.h1
-rw-r--r--arch/arm64/kvm/arm.c26
-rw-r--r--arch/arm64/kvm/hyp/include/nvhe/mm.h1
-rw-r--r--arch/arm64/kvm/hyp/nvhe/mm.c83
-rw-r--r--arch/arm64/kvm/hyp/nvhe/setup.c27
-rw-r--r--arch/arm64/kvm/mmu.c85
6 files changed, 138 insertions, 85 deletions
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 0e1e1ab17b4d..96a80e8f6226 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -168,6 +168,7 @@ int create_hyp_io_mappings(phys_addr_t phys_addr, size_t size,
void __iomem **haddr);
int create_hyp_exec_mappings(phys_addr_t phys_addr, size_t size,
void **haddr);
+int create_hyp_stack(phys_addr_t phys_addr, unsigned long *haddr);
void __init free_hyp_pgds(void);
void stage2_unmap_vm(struct kvm *kvm);
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 3c015bdd35ee..93ada0aae507 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -2283,30 +2283,8 @@ static int __init init_hyp_mode(void)
for_each_possible_cpu(cpu) {
struct kvm_nvhe_init_params *params = per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
char *stack_page = (char *)per_cpu(kvm_arm_hyp_stack_page, cpu);
- unsigned long hyp_addr;
- /*
- * Allocate a contiguous HYP private VA range for the stack
- * and guard page. The allocation is also aligned based on
- * the order of its size.
- */
- err = hyp_alloc_private_va_range(PAGE_SIZE * 2, &hyp_addr);
- if (err) {
- kvm_err("Cannot allocate hyp stack guard page\n");
- goto out_err;
- }
-
- /*
- * Since the stack grows downwards, map the stack to the page
- * at the higher address and leave the lower guard page
- * unbacked.
- *
- * Any valid stack address now has the PAGE_SHIFT bit as 1
- * and addresses corresponding to the guard page have the
- * PAGE_SHIFT bit as 0 - this is used for overflow detection.
- */
- err = __create_hyp_mappings(hyp_addr + PAGE_SIZE, PAGE_SIZE,
- __pa(stack_page), PAGE_HYP);
+ err = create_hyp_stack(__pa(stack_page), &params->stack_hyp_va);
if (err) {
kvm_err("Cannot map hyp stack\n");
goto out_err;
@@ -2319,8 +2297,6 @@ static int __init init_hyp_mode(void)
* has been mapped in the flexible private VA space.
*/
params->stack_pa = __pa(stack_page);
-
- params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE);
}
for_each_possible_cpu(cpu) {
diff --git a/arch/arm64/kvm/hyp/include/nvhe/mm.h b/arch/arm64/kvm/hyp/include/nvhe/mm.h
index d5ec972b5c1e..230e4f2527de 100644
--- a/arch/arm64/kvm/hyp/include/nvhe/mm.h
+++ b/arch/arm64/kvm/hyp/include/nvhe/mm.h
@@ -26,6 +26,7 @@ int pkvm_create_mappings_locked(void *from, void *to, enum kvm_pgtable_prot prot
int __pkvm_create_private_mapping(phys_addr_t phys, size_t size,
enum kvm_pgtable_prot prot,
unsigned long *haddr);
+int pkvm_create_stack(phys_addr_t phys, unsigned long *haddr);
int pkvm_alloc_private_va_range(size_t size, unsigned long *haddr);
#endif /* __KVM_HYP_MM_H */
diff --git a/arch/arm64/kvm/hyp/nvhe/mm.c b/arch/arm64/kvm/hyp/nvhe/mm.c
index 318298eb3d6b..65a7a186d7b2 100644
--- a/arch/arm64/kvm/hyp/nvhe/mm.c
+++ b/arch/arm64/kvm/hyp/nvhe/mm.c
@@ -44,6 +44,27 @@ static int __pkvm_create_mappings(unsigned long start, unsigned long size,
return err;
}
+static int __pkvm_alloc_private_va_range(unsigned long start, size_t size)
+{
+ unsigned long cur;
+
+ hyp_assert_lock_held(&pkvm_pgd_lock);
+
+ if (!start || start < __io_map_base)
+ return -EINVAL;
+
+ /* The allocated size is always a multiple of PAGE_SIZE */
+ cur = start + PAGE_ALIGN(size);
+
+ /* Are we overflowing on the vmemmap ? */
+ if (cur > __hyp_vmemmap)
+ return -ENOMEM;
+
+ __io_map_base = cur;
+
+ return 0;
+}
+
/**
* pkvm_alloc_private_va_range - Allocates a private VA range.
* @size: The size of the VA range to reserve.
@@ -56,27 +77,16 @@ static int __pkvm_create_mappings(unsigned long start, unsigned long size,
*/
int pkvm_alloc_private_va_range(size_t size, unsigned long *haddr)
{
- unsigned long base, addr;
- int ret = 0;
+ unsigned long addr;
+ int ret;
hyp_spin_lock(&pkvm_pgd_lock);
-
- /* Align the allocation based on the order of its size */
- addr = ALIGN(__io_map_base, PAGE_SIZE << get_order(size));
-
- /* The allocated size is always a multiple of PAGE_SIZE */
- base = addr + PAGE_ALIGN(size);
-
- /* Are we overflowing on the vmemmap ? */
- if (!addr || base > __hyp_vmemmap)
- ret = -ENOMEM;
- else {
- __io_map_base = base;
- *haddr = addr;
- }
-
+ addr = __io_map_base;
+ ret = __pkvm_alloc_private_va_range(addr, size);
hyp_spin_unlock(&pkvm_pgd_lock);
+ *haddr = addr;
+
return ret;
}
@@ -340,6 +350,45 @@ int hyp_create_idmap(u32 hyp_va_bits)
return __pkvm_create_mappings(start, end - start, start, PAGE_HYP_EXEC);
}
+int pkvm_create_stack(phys_addr_t phys, unsigned long *haddr)
+{
+ unsigned long addr, prev_base;
+ size_t size;
+ int ret;
+
+ hyp_spin_lock(&pkvm_pgd_lock);
+
+ prev_base = __io_map_base;
+ /*
+ * Efficient stack verification using the PAGE_SHIFT bit implies
+ * an alignment of our allocation on the order of the size.
+ */
+ size = PAGE_SIZE * 2;
+ addr = ALIGN(__io_map_base, size);
+
+ ret = __pkvm_alloc_private_va_range(addr, size);
+ if (!ret) {
+ /*
+ * Since the stack grows downwards, map the stack to the page
+ * at the higher address and leave the lower guard page
+ * unbacked.
+ *
+ * Any valid stack address now has the PAGE_SHIFT bit as 1
+ * and addresses corresponding to the guard page have the
+ * PAGE_SHIFT bit as 0 - this is used for overflow detection.
+ */
+ ret = kvm_pgtable_hyp_map(&pkvm_pgtable, addr + PAGE_SIZE,
+ PAGE_SIZE, phys, PAGE_HYP);
+ if (ret)
+ __io_map_base = prev_base;
+ }
+ hyp_spin_unlock(&pkvm_pgd_lock);
+
+ *haddr = addr + size;
+
+ return ret;
+}
+
static void *admit_host_page(void *arg)
{
struct kvm_hyp_memcache *host_mc = arg;
diff --git a/arch/arm64/kvm/hyp/nvhe/setup.c b/arch/arm64/kvm/hyp/nvhe/setup.c
index bb98630dfeaf..0d5e0a89ddce 100644
--- a/arch/arm64/kvm/hyp/nvhe/setup.c
+++ b/arch/arm64/kvm/hyp/nvhe/setup.c
@@ -113,7 +113,6 @@ static int recreate_hyp_mappings(phys_addr_t phys, unsigned long size,
for (i = 0; i < hyp_nr_cpus; i++) {
struct kvm_nvhe_init_params *params = per_cpu_ptr(&kvm_init_params, i);
- unsigned long hyp_addr;
start = (void *)kern_hyp_va(per_cpu_base[i]);
end = start + PAGE_ALIGN(hyp_percpu_size);
@@ -121,33 +120,9 @@ static int recreate_hyp_mappings(phys_addr_t phys, unsigned long size,
if (ret)
return ret;
- /*
- * Allocate a contiguous HYP private VA range for the stack
- * and guard page. The allocation is also aligned based on
- * the order of its size.
- */
- ret = pkvm_alloc_private_va_range(PAGE_SIZE * 2, &hyp_addr);
+ ret = pkvm_create_stack(params->stack_pa, &params->stack_hyp_va);
if (ret)
return ret;
-
- /*
- * Since the stack grows downwards, map the stack to the page
- * at the higher address and leave the lower guard page
- * unbacked.
- *
- * Any valid stack address now has the PAGE_SHIFT bit as 1
- * and addresses corresponding to the guard page have the
- * PAGE_SHIFT bit as 0 - this is used for overflow detection.
- */
- hyp_spin_lock(&pkvm_pgd_lock);
- ret = kvm_pgtable_hyp_map(&pkvm_pgtable, hyp_addr + PAGE_SIZE,
- PAGE_SIZE, params->stack_pa, PAGE_HYP);
- hyp_spin_unlock(&pkvm_pgd_lock);
- if (ret)
- return ret;
-
- /* Update stack_hyp_va to end of the stack's private VA range */
- params->stack_hyp_va = hyp_addr + (2 * PAGE_SIZE);
}
/*
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 137b775d238b..499555e04732 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -592,6 +592,25 @@ int create_hyp_mappings(void *from, void *to, enum kvm_pgtable_prot prot)
return 0;
}
+static int __hyp_alloc_private_va_range(unsigned long base)
+{
+ lockdep_assert_held(&kvm_hyp_pgd_mutex);
+
+ if (!PAGE_ALIGNED(base))
+ return -EINVAL;
+
+ /*
+ * Verify that BIT(VA_BITS - 1) hasn't been flipped by
+ * allocating the new area, as it would indicate we've
+ * overflowed the idmap/IO address range.
+ */
+ if ((base ^ io_map_base) & BIT(VA_BITS - 1))
+ return -ENOMEM;
+
+ io_map_base = base;
+
+ return 0;
+}
/**
* hyp_alloc_private_va_range - Allocates a private VA range.
@@ -612,26 +631,16 @@ int hyp_alloc_private_va_range(size_t size, unsigned long *haddr)
/*
* This assumes that we have enough space below the idmap
- * page to allocate our VAs. If not, the check below will
- * kick. A potential alternative would be to detect that
- * overflow and switch to an allocation above the idmap.
+ * page to allocate our VAs. If not, the check in
+ * __hyp_alloc_private_va_range() will kick. A potential
+ * alternative would be to detect that overflow and switch
+ * to an allocation above the idmap.
*
* The allocated size is always a multiple of PAGE_SIZE.
*/
- base = io_map_base - PAGE_ALIGN(size);
-
- /* Align the allocation based on the order of its size */
- base = ALIGN_DOWN(base, PAGE_SIZE << get_order(size));
-
- /*
- * Verify that BIT(VA_BITS - 1) hasn't been flipped by
- * allocating the new area, as it would indicate we've
- * overflowed the idmap/IO address range.
- */
- if ((base ^ io_map_base) & BIT(VA_BITS - 1))
- ret = -ENOMEM;
- else
- *haddr = io_map_base = base;
+ size = PAGE_ALIGN(size);
+ base = io_map_base - size;
+ ret = __hyp_alloc_private_va_range(base);
mutex_unlock(&kvm_hyp_pgd_mutex);
@@ -668,6 +677,48 @@ static int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size,
return ret;
}
+int create_hyp_stack(phys_addr_t phys_addr, unsigned long *haddr)
+{
+ unsigned long base;
+ size_t size;
+ int ret;
+
+ mutex_lock(&kvm_hyp_pgd_mutex);
+ /*
+ * Efficient stack verification using the PAGE_SHIFT bit implies
+ * an alignment of our allocation on the order of the size.
+ */
+ size = PAGE_SIZE * 2;
+ base = ALIGN_DOWN(io_map_base - size, size);
+
+ ret = __hyp_alloc_private_va_range(base);
+
+ mutex_unlock(&kvm_hyp_pgd_mutex);
+
+ if (ret) {
+ kvm_err("Cannot allocate hyp stack guard page\n");
+ return ret;
+ }
+
+ /*
+ * Since the stack grows downwards, map the stack to the page
+ * at the higher address and leave the lower guard page
+ * unbacked.
+ *
+ * Any valid stack address now has the PAGE_SHIFT bit as 1
+ * and addresses corresponding to the guard page have the
+ * PAGE_SHIFT bit as 0 - this is used for overflow detection.
+ */
+ ret = __create_hyp_mappings(base + PAGE_SIZE, PAGE_SIZE, phys_addr,
+ PAGE_HYP);
+ if (ret)
+ kvm_err("Cannot map hyp stack\n");
+
+ *haddr = base + size;
+
+ return ret;
+}
+
/**
* create_hyp_io_mappings - Map IO into both kernel and HYP
* @phys_addr: The physical start address which gets mapped
generated by cgit v1.2.3-70-g09d2 (git 2.47.1) at 2025-02-05 16:36:40 +0000