Parse storage keys related device tree entry in early_init_devtree
and enable MMU feature MMU_FTR_PKEY if pkeys are supported.
MMU feature is used instead of CPU feature because this enables us
to group MMU_FTR_KUAP and MMU_FTR_PKEY in asm feature fixup code.
Signed-off-by: Aneesh Kumar K.V <aneesh.ku...@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/pkeys.h | 9 ++++
arch/powerpc/include/asm/mmu.h | 4 ++
arch/powerpc/kernel/prom.c | 6 +++
arch/powerpc/mm/book3s64/pkeys.c | 54 +++++++++++++---------
4 files changed, 50 insertions(+), 23 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/pkeys.h
b/arch/powerpc/include/asm/book3s/64/pkeys.h
index 8174662a9173..c2c7d744e3bb 100644
--- a/arch/powerpc/include/asm/book3s/64/pkeys.h
+++ b/arch/powerpc/include/asm/book3s/64/pkeys.h
@@ -22,4 +22,13 @@ static inline u16 pte_to_pkey_bits(u64 pteflags)
return hash__pte_to_pkey_bits(pteflags);
}
+#ifdef CONFIG_PPC_MEM_KEYS
+extern void pkey_early_init_devtree(void);
+#else
+static inline void pkey_early_init_devtree(void)
+{
+
+}
+#endif
+
#endif /*_ASM_POWERPC_KEYS_H */
diff --git a/arch/powerpc/include/asm/mmu.h b/arch/powerpc/include/asm/mmu.h
index 0699cfeeb8c9..3816e9901f7d 100644
--- a/arch/powerpc/include/asm/mmu.h
+++ b/arch/powerpc/include/asm/mmu.h
@@ -23,6 +23,7 @@
/* Radix page table supported and enabled */
#define MMU_FTR_TYPE_RADIX ASM_CONST(0x00000040)
+#define MMU_FTR_PKEY ASM_CONST(0x00000080)
/*
* Individual features below.
@@ -176,6 +177,9 @@ enum {
MMU_FTR_RADIX_KUAP |
#endif /* CONFIG_PPC_KUAP */
#endif /* CONFIG_PPC_RADIX_MMU */
+#ifdef CONFIG_PPC_MEM_KEYS
+ MMU_FTR_PKEY |
+#endif
0,
};
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 6620f37abe73..d027d1155a65 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -56,6 +56,7 @@
#include <asm/dt_cpu_ftrs.h>
#include <asm/drmem.h>
#include <asm/ultravisor.h>
+#include <asm/pkeys.h>
#include <mm/mmu_decl.h>
@@ -791,6 +792,11 @@ void __init early_init_devtree(void *params)
/* Now try to figure out if we are running on LPAR and so on */
pseries_probe_fw_features();
+ /*
+ * Initialize pkey features and default AMR/IAMR values
+ */
+ pkey_early_init_devtree();
+
#ifdef CONFIG_PPC_PS3
/* Identify PS3 firmware */
if (of_flat_dt_is_compatible(of_get_flat_dt_root(), "sony,ps3"))
diff --git a/arch/powerpc/mm/book3s64/pkeys.c b/arch/powerpc/mm/book3s64/pkeys.c
index 0303df9368e1..36cc4ff8ea5b 100644
--- a/arch/powerpc/mm/book3s64/pkeys.c
+++ b/arch/powerpc/mm/book3s64/pkeys.c
@@ -10,7 +10,8 @@
#include <asm/mmu.h>
#include <asm/setup.h>
#include <linux/pkeys.h>
-#include <linux/of_device.h>
+#include <linux/of_fdt.h>
+
DEFINE_STATIC_KEY_FALSE(pkey_disabled);
DEFINE_STATIC_KEY_FALSE(execute_pkey_disabled);
@@ -38,38 +39,45 @@ static int execute_only_key = 2;
#define PKEY_REG_BITS (sizeof(u64) * 8)
#define pkeyshift(pkey) (PKEY_REG_BITS - ((pkey+1) * AMR_BITS_PER_PKEY))
+static int __init dt_scan_storage_keys(unsigned long node,
+ const char *uname, int depth,
+ void *data)
+{
+ const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
+ const __be32 *prop;
+ int pkeys_total;
+
+ /* We are scanning "cpu" nodes only */
+ if (type == NULL || strcmp(type, "cpu") != 0)
+ return 0;
+
+ prop = of_get_flat_dt_prop(node, "ibm,processor-storage-keys", NULL);
+ if (!prop)
+ return 0;
+ pkeys_total = be32_to_cpu(prop[0]);
+ return pkeys_total;
+}
+
static int scan_pkey_feature(void)
{
- u32 vals[2];
- int pkeys_total = 0;
- struct device_node *cpu;
+ int pkeys_total;
/*
* Pkey is not supported with Radix translation.
*/
- if (radix_enabled())
+ if (early_radix_enabled())
return 0;
- cpu = of_find_node_by_type(NULL, "cpu");
- if (!cpu)
- return 0;
+ pkeys_total = of_scan_flat_dt(dt_scan_storage_keys, NULL);
+ if (pkeys_total == 0) {
- if (of_property_read_u32_array(cpu,
- "ibm,processor-storage-keys", vals, 2)
== 0) {
- /*
- * Since any pkey can be used for data or execute, we will
- * just treat all keys as equal and track them as one entity.
- */
- pkeys_total = vals[0];
- /* Should we check for IAMR support FIXME!! */
- } else {
/*
* Let's assume 32 pkeys on P8 bare metal, if its not defined
by device
* tree. We make this exception since skiboot forgot to expose
this
* property on power8.
*/
if (!firmware_has_feature(FW_FEATURE_LPAR) &&
- cpu_has_feature(CPU_FTRS_POWER8))
+ early_cpu_has_feature(CPU_FTRS_POWER8))
pkeys_total = 32;
}
@@ -82,7 +90,7 @@ static int scan_pkey_feature(void)
return pkeys_total;
}
-static int pkey_initialize(void)
+void __init pkey_early_init_devtree(void)
{
int pkeys_total, i;
@@ -107,9 +115,11 @@ static int pkey_initialize(void)
if (!pkeys_total) {
/* No support for pkey. Mark it disabled */
static_branch_enable(&pkey_disabled);
- return 0;
+ return;
}
+ cur_cpu_spec->mmu_features |= MMU_FTR_PKEY;
+
/*
* The device tree cannot be relied to indicate support for
* execute_disable support. Instead we use a PVR check.
@@ -187,11 +197,9 @@ static int pkey_initialize(void)
*/
initial_allocation_mask |= reserved_allocation_mask;
- return 0;
+ return;
}
-arch_initcall(pkey_initialize);
-
void pkey_mm_init(struct mm_struct *mm)
{
if (static_branch_likely(&pkey_disabled))
--
2.25.3
