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473c3cc86c
Both 4K and 64K pages are supported on powerpc. Parts of the selftest code perform alignment computations based on the PAGE_SIZE macro which is currently hardcoded to 64K for powerpc. This causes some test failures on kernels configured with 4K page size. In some cases, we need to enforce function alignment on page size. Since this can only be done at build time, 64K is used as the alignment factor as that also ensures 4K alignment. Signed-off-by: Sandipan Das <sandipan@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Dave Hansen <dave.hansen@intel.com> Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com> Cc: Florian Weimer <fweimer@redhat.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Ram Pai <linuxram@us.ibm.com> Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Suchanek <msuchanek@suse.de> Cc: Shuah Khan <shuah@kernel.org> Link: http://lkml.kernel.org/r/5dcdfbf3353acdc90f315172e800b49f5ca21299.1585646528.git.sandipan@linux.ibm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
134 lines
3.3 KiB
C
134 lines
3.3 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _PKEYS_POWERPC_H
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#define _PKEYS_POWERPC_H
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#ifndef SYS_mprotect_key
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# define SYS_mprotect_key 386
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#endif
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#ifndef SYS_pkey_alloc
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# define SYS_pkey_alloc 384
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# define SYS_pkey_free 385
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#endif
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#define REG_IP_IDX PT_NIP
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#define REG_TRAPNO PT_TRAP
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#define gregs gp_regs
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#define fpregs fp_regs
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#define si_pkey_offset 0x20
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#undef PKEY_DISABLE_ACCESS
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#define PKEY_DISABLE_ACCESS 0x3 /* disable read and write */
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#undef PKEY_DISABLE_WRITE
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#define PKEY_DISABLE_WRITE 0x2
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#define NR_PKEYS 32
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#define NR_RESERVED_PKEYS_4K 27 /* pkey-0, pkey-1, exec-only-pkey
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and 24 other keys that cannot be
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represented in the PTE */
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#define NR_RESERVED_PKEYS_64K_3KEYS 3 /* PowerNV and KVM: pkey-0,
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pkey-1 and exec-only key */
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#define NR_RESERVED_PKEYS_64K_4KEYS 4 /* PowerVM: pkey-0, pkey-1,
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pkey-31 and exec-only key */
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#define PKEY_BITS_PER_PKEY 2
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#define HPAGE_SIZE (1UL << 24)
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#define PAGE_SIZE sysconf(_SC_PAGESIZE)
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static inline u32 pkey_bit_position(int pkey)
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{
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return (NR_PKEYS - pkey - 1) * PKEY_BITS_PER_PKEY;
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}
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static inline u64 __read_pkey_reg(void)
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{
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u64 pkey_reg;
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asm volatile("mfspr %0, 0xd" : "=r" (pkey_reg));
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return pkey_reg;
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}
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static inline void __write_pkey_reg(u64 pkey_reg)
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{
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u64 amr = pkey_reg;
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dprintf4("%s() changing %016llx to %016llx\n",
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__func__, __read_pkey_reg(), pkey_reg);
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asm volatile("isync; mtspr 0xd, %0; isync"
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: : "r" ((unsigned long)(amr)) : "memory");
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dprintf4("%s() pkey register after changing %016llx to %016llx\n",
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__func__, __read_pkey_reg(), pkey_reg);
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}
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static inline int cpu_has_pkeys(void)
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{
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/* No simple way to determine this */
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return 1;
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}
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static inline bool arch_is_powervm()
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{
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struct stat buf;
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if ((stat("/sys/firmware/devicetree/base/ibm,partition-name", &buf) == 0) &&
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(stat("/sys/firmware/devicetree/base/hmc-managed?", &buf) == 0) &&
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(stat("/sys/firmware/devicetree/base/chosen/qemu,graphic-width", &buf) == -1) )
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return true;
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return false;
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}
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static inline int get_arch_reserved_keys(void)
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{
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if (sysconf(_SC_PAGESIZE) == 4096)
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return NR_RESERVED_PKEYS_4K;
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else
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if (arch_is_powervm())
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return NR_RESERVED_PKEYS_64K_4KEYS;
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else
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return NR_RESERVED_PKEYS_64K_3KEYS;
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}
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void expect_fault_on_read_execonly_key(void *p1, int pkey)
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{
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/*
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* powerpc does not allow userspace to change permissions of exec-only
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* keys since those keys are not allocated by userspace. The signal
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* handler wont be able to reset the permissions, which means the code
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* will infinitely continue to segfault here.
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*/
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return;
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}
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/* 4-byte instructions * 16384 = 64K page */
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#define __page_o_noops() asm(".rept 16384 ; nop; .endr")
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void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey)
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{
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void *ptr;
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int ret;
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dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
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size, prot, pkey);
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pkey_assert(pkey < NR_PKEYS);
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ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
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pkey_assert(ptr != (void *)-1);
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ret = syscall(__NR_subpage_prot, ptr, size, NULL);
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if (ret) {
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perror("subpage_perm");
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return PTR_ERR_ENOTSUP;
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}
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ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
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pkey_assert(!ret);
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record_pkey_malloc(ptr, size, prot);
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dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
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return ptr;
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}
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#endif /* _PKEYS_POWERPC_H */
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