[PATCH v12 13/22] selftests/vm: powerpc implementation for generic abstraction

From: Ram Pai
Date: Wed Feb 21 2018 - 20:57:17 EST


Introduce powerpc implementation for the various
abstractions.

cc: Dave Hansen <dave.hansen@xxxxxxxxx>
cc: Florian Weimer <fweimer@xxxxxxxxxx>
Signed-off-by: Ram Pai <linuxram@xxxxxxxxxx>
---
tools/testing/selftests/vm/pkey-helpers.h | 128 ++++++++++++++++++++++----
tools/testing/selftests/vm/protection_keys.c | 42 +++++---
2 files changed, 136 insertions(+), 34 deletions(-)

diff --git a/tools/testing/selftests/vm/pkey-helpers.h b/tools/testing/selftests/vm/pkey-helpers.h
index c8f5739..c47aead 100644
--- a/tools/testing/selftests/vm/pkey-helpers.h
+++ b/tools/testing/selftests/vm/pkey-helpers.h
@@ -18,27 +18,51 @@
#define u16 uint16_t
#define u32 uint32_t
#define u64 uint64_t
-#define pkey_reg_t u32

-#ifdef __i386__
+#if defined(__i386__) || defined(__x86_64__) /* arch */
+
+#ifdef __i386__ /* arch */
#define SYS_mprotect_key 380
-#define SYS_pkey_alloc 381
-#define SYS_pkey_free 382
+#define SYS_pkey_alloc 381
+#define SYS_pkey_free 382
#define REG_IP_IDX REG_EIP
-#define si_pkey_offset 0x14
-#else
+#elif __x86_64__
#define SYS_mprotect_key 329
-#define SYS_pkey_alloc 330
-#define SYS_pkey_free 331
+#define SYS_pkey_alloc 330
+#define SYS_pkey_free 331
#define REG_IP_IDX REG_RIP
-#define si_pkey_offset 0x20
-#endif
+#endif /* __x86_64__ */
+
+#define NR_PKEYS 16
+#define NR_RESERVED_PKEYS 1
+#define PKEY_BITS_PER_PKEY 2
+#define PKEY_DISABLE_ACCESS 0x1
+#define PKEY_DISABLE_WRITE 0x2
+#define HPAGE_SIZE (1UL<<21)
+#define pkey_reg_t u32

-#define NR_PKEYS 16
-#define PKEY_BITS_PER_PKEY 2
-#define PKEY_DISABLE_ACCESS 0x1
-#define PKEY_DISABLE_WRITE 0x2
-#define HPAGE_SIZE (1UL<<21)
+#elif __powerpc64__ /* arch */
+
+#define SYS_mprotect_key 386
+#define SYS_pkey_alloc 384
+#define SYS_pkey_free 385
+#define REG_IP_IDX PT_NIP
+#define REG_TRAPNO PT_TRAP
+#define gregs gp_regs
+#define fpregs fp_regs
+
+#define NR_PKEYS 32
+#define NR_RESERVED_PKEYS_4K 26
+#define NR_RESERVED_PKEYS_64K 3
+#define PKEY_BITS_PER_PKEY 2
+#define PKEY_DISABLE_ACCESS 0x3 /* disable read and write */
+#define PKEY_DISABLE_WRITE 0x2
+#define HPAGE_SIZE (1UL<<24)
+#define pkey_reg_t u64
+
+#else /* arch */
+ NOT SUPPORTED
+#endif /* arch */

#ifndef DEBUG_LEVEL
#define DEBUG_LEVEL 0
@@ -47,7 +71,11 @@

static inline u32 pkey_to_shift(int pkey)
{
+#if defined(__i386__) || defined(__x86_64__) /* arch */
return pkey * PKEY_BITS_PER_PKEY;
+#elif __powerpc64__ /* arch */
+ return (NR_PKEYS - pkey - 1) * PKEY_BITS_PER_PKEY;
+#endif /* arch */
}

static inline pkey_reg_t reset_bits(int pkey, pkey_reg_t bits)
@@ -111,6 +139,7 @@ static inline void sigsafe_printf(const char *format, ...)
extern pkey_reg_t shadow_pkey_reg;
static inline pkey_reg_t __rdpkey_reg(void)
{
+#if defined(__i386__) || defined(__x86_64__) /* arch */
unsigned int eax, edx;
unsigned int ecx = 0;
pkey_reg_t pkey_reg;
@@ -118,7 +147,13 @@ static inline pkey_reg_t __rdpkey_reg(void)
asm volatile(".byte 0x0f,0x01,0xee\n\t"
: "=a" (eax), "=d" (edx)
: "c" (ecx));
- pkey_reg = eax;
+#elif __powerpc64__ /* arch */
+ pkey_reg_t eax;
+ pkey_reg_t pkey_reg;
+
+ asm volatile("mfspr %0, 0xd" : "=r" ((pkey_reg_t)(eax)));
+#endif /* arch */
+ pkey_reg = (pkey_reg_t)eax;
return pkey_reg;
}

@@ -138,6 +173,7 @@ static inline pkey_reg_t _rdpkey_reg(int line)
static inline void __wrpkey_reg(pkey_reg_t pkey_reg)
{
pkey_reg_t eax = pkey_reg;
+#if defined(__i386__) || defined(__x86_64__) /* arch */
pkey_reg_t ecx = 0;
pkey_reg_t edx = 0;

@@ -146,6 +182,14 @@ static inline void __wrpkey_reg(pkey_reg_t pkey_reg)
asm volatile(".byte 0x0f,0x01,0xef\n\t"
: : "a" (eax), "c" (ecx), "d" (edx));
assert(pkey_reg == __rdpkey_reg());
+
+#elif __powerpc64__ /* arch */
+ dprintf4("%s() changing %llx to %llx\n",
+ __func__, __rdpkey_reg(), pkey_reg);
+ asm volatile("mtspr 0xd, %0" : : "r" ((unsigned long)(eax)) : "memory");
+#endif /* arch */
+ dprintf4("%s() pkey register after changing %016lx to %016lx\n",
+ __func__, __rdpkey_reg(), pkey_reg);
}

static inline void wrpkey_reg(pkey_reg_t pkey_reg)
@@ -192,6 +236,8 @@ static inline void __pkey_write_allow(int pkey, int do_allow_write)
dprintf4("pkey_reg now: %08x\n", rdpkey_reg());
}

+#if defined(__i386__) || defined(__x86_64__) /* arch */
+
#define PAGE_SIZE 4096
#define MB (1<<20)

@@ -274,8 +320,18 @@ static inline void __page_o_noops(void)
/* 8-bytes of instruction * 512 bytes = 1 page */
asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
}
+#elif __powerpc64__ /* arch */

-#endif /* _PKEYS_HELPER_H */
+#define PAGE_SIZE (0x1UL << 16)
+static inline int cpu_has_pku(void)
+{
+ return 1;
+}
+
+/* 8-bytes of instruction * 16384bytes = 1 page */
+#define __page_o_noops() asm(".rept 16384 ; nop; .endr")
+
+#endif /* arch */

#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
#define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1))
@@ -307,11 +363,47 @@ static inline void __page_o_noops(void)

static inline int open_hugepage_file(int flag)
{
- return open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages",
+ int fd;
+
+#if defined(__i386__) || defined(__x86_64__) /* arch */
+ fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages",
O_RDONLY);
+#elif __powerpc64__ /* arch */
+ fd = open("/sys/kernel/mm/hugepages/hugepages-16384kB/nr_hugepages",
+ O_RDONLY);
+#else /* arch */
+ NOT SUPPORTED
+#endif /* arch */
+ return fd;
}

static inline int get_start_key(void)
{
+#if defined(__i386__) || defined(__x86_64__) /* arch */
return 1;
+#elif __powerpc64__ /* arch */
+ return 0;
+#else /* arch */
+ NOT SUPPORTED
+#endif /* arch */
+}
+
+static inline u32 *siginfo_get_pkey_ptr(siginfo_t *si)
+{
+#ifdef si_pkey
+ return &si->si_pkey;
+#else
+
+#ifdef __i386__ /* arch */
+#define si_pkey_offset 0x14
+#elif __x86_64__ /*arch */
+#define si_pkey_offset 0x1C
+#elif __powerpc64__ /*arch */
+#define si_pkey_offset 0x1C
+#endif /*arch */
+
+ return (u32 *)(((u8 *)si) + si_pkey_offset);
+#endif
}
+
+#endif /* _PKEYS_HELPER_H */
diff --git a/tools/testing/selftests/vm/protection_keys.c b/tools/testing/selftests/vm/protection_keys.c
index 6fdd8f5..c4c73e6 100644
--- a/tools/testing/selftests/vm/protection_keys.c
+++ b/tools/testing/selftests/vm/protection_keys.c
@@ -186,17 +186,18 @@ void dump_mem(void *dumpme, int len_bytes)

int pkey_faults;
int last_si_pkey = -1;
+void pkey_access_allow(int pkey);
void signal_handler(int signum, siginfo_t *si, void *vucontext)
{
ucontext_t *uctxt = vucontext;
int trapno;
unsigned long ip;
char *fpregs;
+#if defined(__i386__) || defined(__x86_64__) /* arch */
pkey_reg_t *pkey_reg_ptr;
- u64 siginfo_pkey;
+#endif /* defined(__i386__) || defined(__x86_64__) */
+ u32 siginfo_pkey;
u32 *si_pkey_ptr;
- int pkey_reg_offset;
- fpregset_t fpregset;

dprint_in_signal = 1;
dprintf1(">>>>===============SIGSEGV============================\n");
@@ -206,12 +207,14 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext)

trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO];
ip = uctxt->uc_mcontext.gregs[REG_IP_IDX];
- fpregset = uctxt->uc_mcontext.fpregs;
- fpregs = (void *)fpregset;
+ fpregs = (char *) uctxt->uc_mcontext.fpregs;

dprintf2("%s() trapno: %d ip: 0x%016lx info->si_code: %s/%d\n",
__func__, trapno, ip, si_code_str(si->si_code),
si->si_code);
+
+#if defined(__i386__) || defined(__x86_64__) /* arch */
+
#ifdef __i386__
/*
* 32-bit has some extra padding so that userspace can tell whether
@@ -219,22 +222,23 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext)
* state. We just assume that it is here.
*/
fpregs += 0x70;
-#endif
- pkey_reg_offset = pkey_reg_xstate_offset();
- pkey_reg_ptr = (void *)(&fpregs[pkey_reg_offset]);
+#endif /* __i386__ */

- dprintf1("siginfo: %p\n", si);
- dprintf1(" fpregs: %p\n", fpregs);
+ pkey_reg_ptr = (void *)(&fpregs[pkey_reg_xstate_offset()]);
/*
- * If we got a PKEY fault, we *HAVE* to have at least one bit set in
+ * If we got a key fault, we *HAVE* to have at least one bit set in
* here.
*/
dprintf1("pkey_reg_xstate_offset: %d\n", pkey_reg_xstate_offset());
if (DEBUG_LEVEL > 4)
dump_mem(pkey_reg_ptr - 128, 256);
pkey_assert(*pkey_reg_ptr);
+#endif /* defined(__i386__) || defined(__x86_64__) */

- si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
+ dprintf1("siginfo: %p\n", si);
+ dprintf1(" fpregs: %p\n", fpregs);
+
+ si_pkey_ptr = siginfo_get_pkey_ptr(si);
dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
dump_mem(si_pkey_ptr - 8, 24);
siginfo_pkey = *si_pkey_ptr;
@@ -248,19 +252,25 @@ void signal_handler(int signum, siginfo_t *si, void *vucontext)
exit(4);
}

- dprintf1("signal pkey_reg from xsave: %016lx\n", *pkey_reg_ptr);
/*
* need __rdpkey_reg() version so we do not do shadow_pkey_reg
* checking
*/
dprintf1("signal pkey_reg from pkey_reg: %016lx\n", __rdpkey_reg());
- dprintf1("pkey from siginfo: %jx\n", siginfo_pkey);
- *(u64 *)pkey_reg_ptr = 0x00000000;
+ dprintf1("pkey from siginfo: %lx\n", siginfo_pkey);
+#if defined(__i386__) || defined(__x86_64__) /* arch */
+ dprintf1("signal pkey_reg from xsave: %016lx\n", *pkey_reg_ptr);
+ *(u64 *)pkey_reg_ptr &= reset_bits(siginfo_pkey,
+ PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE);
+#elif __powerpc64__
+ pkey_access_allow(siginfo_pkey);
+#endif
+ shadow_pkey_reg &= reset_bits(siginfo_pkey,
+ PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE);
dprintf1("WARNING: set PKEY_REG=0 to allow faulting instruction "
"to continue\n");
pkey_faults++;
dprintf1("<<<<==================================================\n");
- return;
}

int wait_all_children(void)
--
1.7.1