projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 589944b5 RP |
1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | ||
| 3 | #ifndef _PKEYS_POWERPC_H | |
| 4 | #define _PKEYS_POWERPC_H | |
| 5 | ||
| 6 | #ifndef SYS_mprotect_key | |
| 7 | # define SYS_mprotect_key 386 | |
| 8 | #endif | |
| 9 | #ifndef SYS_pkey_alloc | |
| 10 | # define SYS_pkey_alloc 384 | |
| 11 | # define SYS_pkey_free 385 | |
| 12 | #endif | |
| 13 | #define REG_IP_IDX PT_NIP | |
| 14 | #define REG_TRAPNO PT_TRAP | |
| 15 | #define gregs gp_regs | |
| 16 | #define fpregs fp_regs | |
| 17 | #define si_pkey_offset 0x20 | |
| 18 | ||
| e9506394 RP |
19 | #undef PKEY_DISABLE_ACCESS |
| 20 | #define PKEY_DISABLE_ACCESS 0x3 /* disable read and write */ | |
| 589944b5 | 21 | |
| e9506394 RP |
22 | #undef PKEY_DISABLE_WRITE |
| 23 | #define PKEY_DISABLE_WRITE 0x2 | |
| 589944b5 RP |
24 | |
| 25 | #define NR_PKEYS 32 | |
| 26 | #define NR_RESERVED_PKEYS_4K 27 /* pkey-0, pkey-1, exec-only-pkey | |
| 27 | and 24 other keys that cannot be | |
| 28 | represented in the PTE */ | |
| c63e5e7f DNR |
29 | #define NR_RESERVED_PKEYS_64K_3KEYS 3 /* PowerNV and KVM: pkey-0, |
| 30 | pkey-1 and exec-only key */ | |
| 31 | #define NR_RESERVED_PKEYS_64K_4KEYS 4 /* PowerVM: pkey-0, pkey-1, | |
| 32 | pkey-31 and exec-only key */ | |
| 589944b5 RP |
33 | #define PKEY_BITS_PER_PKEY 2 |
| 34 | #define HPAGE_SIZE (1UL << 24) | |
| 473c3cc8 | 35 | #define PAGE_SIZE sysconf(_SC_PAGESIZE) |
| 589944b5 RP |
36 | |
| 37 | static inline u32 pkey_bit_position(int pkey) | |
| 38 | { | |
| 39 | return (NR_PKEYS - pkey - 1) * PKEY_BITS_PER_PKEY; | |
| 40 | } | |
| 41 | ||
| 42 | static inline u64 __read_pkey_reg(void) | |
| 43 | { | |
| 44 | u64 pkey_reg; | |
| 45 | ||
| 46 | asm volatile("mfspr %0, 0xd" : "=r" (pkey_reg)); | |
| 47 | ||
| 48 | return pkey_reg; | |
| 49 | } | |
| 50 | ||
| 51 | static inline void __write_pkey_reg(u64 pkey_reg) | |
| 52 | { | |
| 53 | u64 amr = pkey_reg; | |
| 54 | ||
| 55 | dprintf4("%s() changing %016llx to %016llx\n", | |
| 56 | __func__, __read_pkey_reg(), pkey_reg); | |
| 57 | ||
| 58 | asm volatile("isync; mtspr 0xd, %0; isync" | |
| 59 | : : "r" ((unsigned long)(amr)) : "memory"); | |
| 60 | ||
| 61 | dprintf4("%s() pkey register after changing %016llx to %016llx\n", | |
| 62 | __func__, __read_pkey_reg(), pkey_reg); | |
| 63 | } | |
| 64 | ||
| 94c8a223 | 65 | static inline int cpu_has_pkeys(void) |
| 589944b5 | 66 | { |
| 94c8a223 | 67 | /* No simple way to determine this */ |
| 589944b5 RP |
68 | return 1; |
| 69 | } | |
| 70 | ||
| c63e5e7f DNR |
71 | static inline bool arch_is_powervm() |
| 72 | { | |
| 73 | struct stat buf; | |
| 74 | ||
| 75 | if ((stat("/sys/firmware/devicetree/base/ibm,partition-name", &buf) == 0) && | |
| 76 | (stat("/sys/firmware/devicetree/base/hmc-managed?", &buf) == 0) && | |
| 77 | (stat("/sys/firmware/devicetree/base/chosen/qemu,graphic-width", &buf) == -1) ) | |
| 78 | return true; | |
| 79 | ||
| 80 | return false; | |
| 81 | } | |
| 82 | ||
| 589944b5 RP |
83 | static inline int get_arch_reserved_keys(void) |
| 84 | { | |
| 85 | if (sysconf(_SC_PAGESIZE) == 4096) | |
| 86 | return NR_RESERVED_PKEYS_4K; | |
| 87 | else | |
| c63e5e7f DNR |
88 | if (arch_is_powervm()) |
| 89 | return NR_RESERVED_PKEYS_64K_4KEYS; | |
| 90 | else | |
| 91 | return NR_RESERVED_PKEYS_64K_3KEYS; | |
| 589944b5 RP |
92 | } |
| 93 | ||
| 94 | void expect_fault_on_read_execonly_key(void *p1, int pkey) | |
| 95 | { | |
| 96 | /* | |
| 97 | * powerpc does not allow userspace to change permissions of exec-only | |
| 98 | * keys since those keys are not allocated by userspace. The signal | |
| 99 | * handler wont be able to reset the permissions, which means the code | |
| 100 | * will infinitely continue to segfault here. | |
| 101 | */ | |
| 102 | return; | |
| 103 | } | |
| 104 | ||
| 105 | /* 4-byte instructions * 16384 = 64K page */ | |
| 106 | #define __page_o_noops() asm(".rept 16384 ; nop; .endr") | |
| 107 | ||
| 6e2c2d0f RP |
108 | void *malloc_pkey_with_mprotect_subpage(long size, int prot, u16 pkey) |
| 109 | { | |
| 110 | void *ptr; | |
| 111 | int ret; | |
| 112 | ||
| 113 | dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__, | |
| 114 | size, prot, pkey); | |
| 115 | pkey_assert(pkey < NR_PKEYS); | |
| 116 | ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); | |
| 117 | pkey_assert(ptr != (void *)-1); | |
| 118 | ||
| 119 | ret = syscall(__NR_subpage_prot, ptr, size, NULL); | |
| 120 | if (ret) { | |
| 121 | perror("subpage_perm"); | |
| 122 | return PTR_ERR_ENOTSUP; | |
| 123 | } | |
| 124 | ||
| 125 | ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey); | |
| 126 | pkey_assert(!ret); | |
| 127 | record_pkey_malloc(ptr, size, prot); | |
| 128 | ||
| 129 | dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr); | |
| 130 | return ptr; | |
| 131 | } | |
| 132 | ||
| 589944b5 | 133 | #endif /* _PKEYS_POWERPC_H */ |