Commit d3cd91fb authored by Aneesh Kumar K.V's avatar Aneesh Kumar K.V Committed by Michael Ellerman
Browse files

powerpc/book3s64/pkeys: Add MMU_FTR_PKEY 



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: default avatarAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200709032946.881753-14-aneesh.kumar@linux.ibm.com
parent 3e4352ae

arch/powerpc/include/asm/book3s/64/mmu.h

+6 −0
Original line number Diff line number Diff line
@@ -214,6 +214,12 @@ extern int mmu_io_psize; 
void mmu_early_init_devtree(void);

void hash__early_init_devtree(void);

void radix__early_init_devtree(void);

#ifdef CONFIG_PPC_MEM_KEYS

void pkey_early_init_devtree(void);

#else

static inline void pkey_early_init_devtree(void) {}

#endif



extern void hash__early_init_mmu(void);

extern void radix__early_init_mmu(void);

static inline void __init early_init_mmu(void)

arch/powerpc/include/asm/mmu.h

+10 −0
Original line number Diff line number Diff line
@@ -28,6 +28,11 @@ 
 * Individual features below.

 */



/*

 * Support for memory protection keys.

 */

#define MMU_FTR_PKEY			ASM_CONST(0x00000800)



/* Guest Translation Shootdown Enable */

#define MMU_FTR_GTSE			ASM_CONST(0x00001000)
@@ -181,6 +186,9 @@ enum { 
		MMU_FTR_RADIX_KUAP |

#endif /* CONFIG_PPC_KUAP */

#endif /* CONFIG_PPC_RADIX_MMU */

#ifdef CONFIG_PPC_MEM_KEYS

	MMU_FTR_PKEY |

#endif

		0,

};
@@ -360,6 +368,8 @@ extern void setup_initial_memory_limit(phys_addr_t first_memblock_base, 
				       phys_addr_t first_memblock_size);

static inline void mmu_early_init_devtree(void) { }



static inline void pkey_early_init_devtree(void) {}



extern void *abatron_pteptrs[2];

#endif /* __ASSEMBLY__ */

#endif

arch/powerpc/kernel/prom.c

+5 −0
Original line number Diff line number Diff line
@@ -815,6 +815,11 @@ 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"))

arch/powerpc/mm/book3s64/pkeys.c

+30 −22
Original line number Diff line number Diff line
@@ -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);

int  num_pkey;		/* Max number of pkeys supported */
@@ -46,31 +47,38 @@ 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 scan_pkey_feature(void)

static int __init dt_scan_storage_keys(unsigned long node,

				       const char *uname, int depth,

				       void *data)

{

	u32 vals[2];

	int pkeys_total = 0;

	struct device_node *cpu;

	const char *type = of_get_flat_dt_prop(node, "device_type", NULL);

	const __be32 *prop;

	int *pkeys_total = (int *) data;



	/*

	 * Pkey is not supported with Radix translation.

	 */

	if (radix_enabled())

	/* We are scanning "cpu" nodes only */

	if (type == NULL || strcmp(type, "cpu") != 0)

		return 0;



	cpu = of_find_node_by_type(NULL, "cpu");

	if (!cpu)

	prop = of_get_flat_dt_prop(node, "ibm,processor-storage-keys", NULL);

	if (!prop)

		return 0;

	*pkeys_total = be32_to_cpu(prop[0]);

	return 1;

}



static int scan_pkey_feature(void)

{

	int ret;

	int 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.

	 * Pkey is not supported with Radix translation.

	 */

		pkeys_total = vals[0];

	} else {

	if (early_radix_enabled())

		return 0;



	ret = of_scan_flat_dt(dt_scan_storage_keys, &pkeys_total);

	if (ret == 0) {

		/*

		 * Let's assume 32 pkeys on P8/P9 bare metal, if its not defined by device

		 * tree. We make this exception since some version of skiboot forgot to
@@ -94,7 +102,7 @@ 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;
@@ -119,9 +127,11 @@ 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.
@@ -201,11 +211,9 @@ 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))

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