helper functions to handler shadow pkey register
cc: Dave Hansen <dave.hansen@xxxxxxxxx>
cc: Florian Weimer <fweimer@xxxxxxxxxx>
Signed-off-by: Ram Pai <linuxram@xxxxxxxxxx>
Signed-off-by: Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxx>
---
tools/testing/selftests/vm/pkey-helpers.h | 29 ++++++++++++++++++++++
tools/testing/selftests/vm/pkey-x86.h | 5 ++++
tools/testing/selftests/vm/protection_keys.c | 34 ++++++++++++++++---------
3 files changed, 56 insertions(+), 12 deletions(-)
diff --git a/tools/testing/selftests/vm/pkey-helpers.h b/tools/testing/selftests/vm/pkey-helpers.h
index 2a1a024..ada0146 100644
--- a/tools/testing/selftests/vm/pkey-helpers.h
+++ b/tools/testing/selftests/vm/pkey-helpers.h
@@ -80,6 +80,35 @@ static inline void sigsafe_printf(const char *format, ...)
#error Architecture not supported
#endif /* arch */
+static inline pkey_reg_t clear_pkey_flags(int pkey, pkey_reg_t flags)
+{
+ u32 shift = pkey_bit_position(pkey);
+
+ return ~(flags << shift);
+}
+
+/*
+ * Takes pkey flags and puts them at the right bit position for the given key so
+ * that the result can be ORed into the register.
+ */
+static inline pkey_reg_t left_shift_bits(int pkey, pkey_reg_t bits)
+{
+ u32 shift = pkey_bit_position(pkey);
+
+ return (bits << shift);
+}
+
+/*
+ * Takes pkey register values and puts the flags for the given pkey at the least
+ * significant bits of the returned value.
+ */
+static inline pkey_reg_t right_shift_bits(int pkey, pkey_reg_t bits)
+{
+ u32 shift = pkey_bit_position(pkey);
+
+ return (bits >> shift);
+}
+
extern pkey_reg_t shadow_pkey_reg;
static inline pkey_reg_t _read_pkey_reg(int line)
diff --git a/tools/testing/selftests/vm/pkey-x86.h b/tools/testing/selftests/vm/pkey-x86.h
index 5f40901..2b3780d 100644
--- a/tools/testing/selftests/vm/pkey-x86.h
+++ b/tools/testing/selftests/vm/pkey-x86.h
@@ -49,6 +49,11 @@
#define pkey_reg_t u32
#define PKEY_REG_FMT "%016x"
+static inline u32 pkey_bit_position(int pkey)
+{
+ return pkey * PKEY_BITS_PER_PKEY;
+}
+
static inline void __page_o_noops(void)
{
/* 8-bytes of instruction * 512 bytes = 1 page */
diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 90b3a41..57340b3 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -342,7 +342,7 @@ static u32 hw_pkey_get(int pkey, unsigned long flags)
__func__, pkey, flags, 0, 0);
dprintf2("%s() raw pkey_reg: "PKEY_REG_FMT"\n", __func__, pkey_reg);
- shifted_pkey_reg = (pkey_reg >> (pkey * PKEY_BITS_PER_PKEY));
+ shifted_pkey_reg = right_shift_bits(pkey, pkey_reg);
dprintf2("%s() shifted_pkey_reg: "PKEY_REG_FMT"\n", __func__,
shifted_pkey_reg);
masked_pkey_reg = shifted_pkey_reg & mask;
@@ -366,9 +366,9 @@ static int hw_pkey_set(int pkey, unsigned long rights, unsigned long flags)
/* copy old pkey_reg */
new_pkey_reg = old_pkey_reg;
/* mask out bits from pkey in old value: */
- new_pkey_reg &= ~(mask << (pkey * PKEY_BITS_PER_PKEY));
+ new_pkey_reg &= clear_pkey_flags(pkey, mask);
/* OR in new bits for pkey: */
- new_pkey_reg |= (rights << (pkey * PKEY_BITS_PER_PKEY));
+ new_pkey_reg |= left_shift_bits(pkey, rights);
__write_pkey_reg(new_pkey_reg);
@@ -402,7 +402,7 @@ void pkey_disable_set(int pkey, int flags)
ret = hw_pkey_set(pkey, pkey_rights, syscall_flags);
assert(!ret);
/*pkey_reg and flags have the same format */
- shadow_pkey_reg |= flags << (pkey * 2);
+ shadow_pkey_reg |= left_shift_bits(pkey, flags);
dprintf1("%s(%d) shadow: 0x"PKEY_REG_FMT"\n",
__func__, pkey, shadow_pkey_reg);
@@ -436,7 +436,7 @@ void pkey_disable_clear(int pkey, int flags)
pkey_rights |= flags;
ret = hw_pkey_set(pkey, pkey_rights, 0);
- shadow_pkey_reg &= ~(flags << (pkey * 2));
+ shadow_pkey_reg &= clear_pkey_flags(pkey, flags);
pkey_assert(ret >= 0);
pkey_rights = hw_pkey_get(pkey, syscall_flags);
@@ -494,6 +494,21 @@ int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
return ret;
}
+void pkey_setup_shadow(void)
+{
+ shadow_pkey_reg = __read_pkey_reg();
+}
+
+void pkey_reset_shadow(u32 key)
+{
+ shadow_pkey_reg &= clear_pkey_flags(key, 0x3);
+}
+
+void pkey_set_shadow(u32 key, u64 init_val)
+{
+ shadow_pkey_reg |= left_shift_bits(key, init_val);
+}
+
int alloc_pkey(void)
{
int ret;
@@ -512,7 +527,7 @@ int alloc_pkey(void)
shadow_pkey_reg);
if (ret) {
/* clear both the bits: */
- shadow_pkey_reg &= ~(0x3 << (ret * 2));
+ pkey_reset_shadow(ret);
dprintf4("%s()::%d, ret: %d pkey_reg: 0x"PKEY_REG_FMT
" shadow: 0x"PKEY_REG_FMT"\n",
__func__,
@@ -522,7 +537,7 @@ int alloc_pkey(void)
* move the new state in from init_val
* (remember, we cheated and init_val == pkey_reg format)
*/
- shadow_pkey_reg |= (init_val << (ret * 2));
+ pkey_set_shadow(ret, init_val);
}
dprintf4("%s()::%d, ret: %d pkey_reg: 0x"PKEY_REG_FMT
" shadow: 0x"PKEY_REG_FMT"\n",
@@ -1403,11 +1418,6 @@ void run_tests_once(void)
iteration_nr++;
}
-void pkey_setup_shadow(void)
-{
- shadow_pkey_reg = __read_pkey_reg();
-}
-
int main(void)
{
int nr_iterations = 22;
--
1.7.1
