diff options
Diffstat (limited to 'tools/testing/selftests/rseq/rseq-arm.h')
| -rw-r--r-- | tools/testing/selftests/rseq/rseq-arm.h | 827 |
1 files changed, 827 insertions, 0 deletions
diff --git a/tools/testing/selftests/rseq/rseq-arm.h b/tools/testing/selftests/rseq/rseq-arm.h new file mode 100644 index 000000000..893a11eca --- /dev/null +++ b/tools/testing/selftests/rseq/rseq-arm.h @@ -0,0 +1,827 @@ +/* SPDX-License-Identifier: LGPL-2.1 OR MIT */ +/* + * rseq-arm.h + * + * (C) Copyright 2016-2018 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> + */ + +/* + * - ARM little endian + * + * RSEQ_SIG uses the udf A32 instruction with an uncommon immediate operand + * value 0x5de3. This traps if user-space reaches this instruction by mistake, + * and the uncommon operand ensures the kernel does not move the instruction + * pointer to attacker-controlled code on rseq abort. + * + * The instruction pattern in the A32 instruction set is: + * + * e7f5def3 udf #24035 ; 0x5de3 + * + * This translates to the following instruction pattern in the T16 instruction + * set: + * + * little endian: + * def3 udf #243 ; 0xf3 + * e7f5 b.n <7f5> + * + * - ARMv6+ big endian (BE8): + * + * ARMv6+ -mbig-endian generates mixed endianness code vs data: little-endian + * code and big-endian data. The data value of the signature needs to have its + * byte order reversed to generate the trap instruction: + * + * Data: 0xf3def5e7 + * + * Translates to this A32 instruction pattern: + * + * e7f5def3 udf #24035 ; 0x5de3 + * + * Translates to this T16 instruction pattern: + * + * def3 udf #243 ; 0xf3 + * e7f5 b.n <7f5> + * + * - Prior to ARMv6 big endian (BE32): + * + * Prior to ARMv6, -mbig-endian generates big-endian code and data + * (which match), so the endianness of the data representation of the + * signature should not be reversed. However, the choice between BE32 + * and BE8 is done by the linker, so we cannot know whether code and + * data endianness will be mixed before the linker is invoked. So rather + * than try to play tricks with the linker, the rseq signature is simply + * data (not a trap instruction) prior to ARMv6 on big endian. This is + * why the signature is expressed as data (.word) rather than as + * instruction (.inst) in assembler. + */ + +#ifdef __ARMEB__ +#define RSEQ_SIG 0xf3def5e7 /* udf #24035 ; 0x5de3 (ARMv6+) */ +#else +#define RSEQ_SIG 0xe7f5def3 /* udf #24035 ; 0x5de3 */ +#endif + +#define rseq_smp_mb() __asm__ __volatile__ ("dmb" ::: "memory", "cc") +#define rseq_smp_rmb() __asm__ __volatile__ ("dmb" ::: "memory", "cc") +#define rseq_smp_wmb() __asm__ __volatile__ ("dmb" ::: "memory", "cc") + +#define rseq_smp_load_acquire(p) \ +__extension__ ({ \ + __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \ + rseq_smp_mb(); \ + ____p1; \ +}) + +#define rseq_smp_acquire__after_ctrl_dep() rseq_smp_rmb() + +#define rseq_smp_store_release(p, v) \ +do { \ + rseq_smp_mb(); \ + RSEQ_WRITE_ONCE(*p, v); \ +} while (0) + +#ifdef RSEQ_SKIP_FASTPATH +#include "rseq-skip.h" +#else /* !RSEQ_SKIP_FASTPATH */ + +#define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip, \ + post_commit_offset, abort_ip) \ + ".pushsection __rseq_cs, \"aw\"\n\t" \ + ".balign 32\n\t" \ + __rseq_str(label) ":\n\t" \ + ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ + ".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \ + ".popsection\n\t" \ + ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ + ".word " __rseq_str(label) "b, 0x0\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ + (post_commit_ip - start_ip), abort_ip) + +/* + * Exit points of a rseq critical section consist of all instructions outside + * of the critical section where a critical section can either branch to or + * reach through the normal course of its execution. The abort IP and the + * post-commit IP are already part of the __rseq_cs section and should not be + * explicitly defined as additional exit points. Knowing all exit points is + * useful to assist debuggers stepping over the critical section. + */ +#define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ + ".pushsection __rseq_exit_point_array, \"aw\"\n\t" \ + ".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(exit_ip) ", 0x0\n\t" \ + ".popsection\n\t" + +#define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ + RSEQ_INJECT_ASM(1) \ + "adr r0, " __rseq_str(cs_label) "\n\t" \ + "str r0, %[" __rseq_str(rseq_cs) "]\n\t" \ + __rseq_str(label) ":\n\t" + +#define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \ + RSEQ_INJECT_ASM(2) \ + "ldr r0, %[" __rseq_str(current_cpu_id) "]\n\t" \ + "cmp %[" __rseq_str(cpu_id) "], r0\n\t" \ + "bne " __rseq_str(label) "\n\t" + +#define __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \ + abort_label, version, flags, \ + start_ip, post_commit_offset, abort_ip) \ + ".balign 32\n\t" \ + __rseq_str(table_label) ":\n\t" \ + ".word " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ + ".word " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) ", 0x0\n\t" \ + ".word " __rseq_str(RSEQ_SIG) "\n\t" \ + __rseq_str(label) ":\n\t" \ + teardown \ + "b %l[" __rseq_str(abort_label) "]\n\t" + +#define RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, abort_label, \ + start_ip, post_commit_ip, abort_ip) \ + __RSEQ_ASM_DEFINE_ABORT(table_label, label, teardown, \ + abort_label, 0x0, 0x0, start_ip, \ + (post_commit_ip - start_ip), abort_ip) + +#define RSEQ_ASM_DEFINE_CMPFAIL(label, teardown, cmpfail_label) \ + __rseq_str(label) ":\n\t" \ + teardown \ + "b %l[" __rseq_str(cmpfail_label) "]\n\t" + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[error2]\n\t" +#endif + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (rseq_get_abi()->cpu_id), + [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr), + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot, + long voffp, intptr_t *load, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expectnot], r0\n\t" + "beq %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "ldr r0, %[v]\n\t" + "cmp %[expectnot], r0\n\t" + "beq %l[error2]\n\t" +#endif + "str r0, %[load]\n\t" + "add r0, %[voffp]\n\t" + "ldr r0, [r0]\n\t" + /* final store */ + "str r0, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(5) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (rseq_get_abi()->cpu_id), + [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr), + /* final store input */ + [v] "m" (*v), + [expectnot] "r" (expectnot), + [voffp] "Ir" (voffp), + [load] "m" (*load) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_addv(intptr_t *v, intptr_t count, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) +#endif + "ldr r0, %[v]\n\t" + "add r0, %[count]\n\t" + /* final store */ + "str r0, %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(4) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (rseq_get_abi()->cpu_id), + [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr), + [v] "m" (*v), + [count] "Ir" (count) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort +#ifdef RSEQ_COMPARE_TWICE + , error1 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[error2]\n\t" +#endif + /* try store */ + "str %[newv2], %[v2]\n\t" + RSEQ_INJECT_ASM(5) + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (rseq_get_abi()->cpu_id), + [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr), + /* try store input */ + [v2] "m" (*v2), + [newv2] "r" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t newv2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[error2]\n\t" +#endif + /* try store */ + "str %[newv2], %[v2]\n\t" + RSEQ_INJECT_ASM(5) + "dmb\n\t" /* full mb provides store-release */ + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (rseq_get_abi()->cpu_id), + [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr), + /* try store input */ + [v2] "m" (*v2), + [newv2] "r" (newv2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect, + intptr_t *v2, intptr_t expect2, + intptr_t newv, int cpu) +{ + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error3]) +#endif + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(4) + "ldr r0, %[v2]\n\t" + "cmp %[expect2], r0\n\t" + "bne %l[cmpfail]\n\t" + RSEQ_INJECT_ASM(5) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, %l[error1]) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne %l[error2]\n\t" + "ldr r0, %[v2]\n\t" + "cmp %[expect2], r0\n\t" + "bne %l[error3]\n\t" +#endif + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + "b 5f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, "", abort, 1b, 2b, 4f) + "5:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (rseq_get_abi()->cpu_id), + [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr), + /* cmp2 input */ + [v2] "m" (*v2), + [expect2] "r" (expect2), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2, error3 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("1st expected value comparison failed"); +error3: + rseq_after_asm_goto(); + rseq_bug("2nd expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + uint32_t rseq_scratch[3]; + + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + "str %[src], %[rseq_scratch0]\n\t" + "str %[dst], %[rseq_scratch1]\n\t" + "str %[len], %[rseq_scratch2]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne 5f\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne 7f\n\t" +#endif + /* try memcpy */ + "cmp %[len], #0\n\t" \ + "beq 333f\n\t" \ + "222:\n\t" \ + "ldrb %%r0, [%[src]]\n\t" \ + "strb %%r0, [%[dst]]\n\t" \ + "adds %[src], #1\n\t" \ + "adds %[dst], #1\n\t" \ + "subs %[len], #1\n\t" \ + "bne 222b\n\t" \ + "333:\n\t" \ + RSEQ_INJECT_ASM(5) + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t" + "b 8f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + abort, 1b, 2b, 4f) + RSEQ_ASM_DEFINE_CMPFAIL(5, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + cmpfail) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_CMPFAIL(6, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + error1) + RSEQ_ASM_DEFINE_CMPFAIL(7, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + error2) +#endif + "8:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (rseq_get_abi()->cpu_id), + [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len), + [rseq_scratch0] "m" (rseq_scratch[0]), + [rseq_scratch1] "m" (rseq_scratch[1]), + [rseq_scratch2] "m" (rseq_scratch[2]) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +static inline __attribute__((always_inline)) +int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect, + void *dst, void *src, size_t len, + intptr_t newv, int cpu) +{ + uint32_t rseq_scratch[3]; + + RSEQ_INJECT_C(9) + + __asm__ __volatile__ goto ( + RSEQ_ASM_DEFINE_TABLE(9, 1f, 2f, 4f) /* start, commit, abort */ + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[cmpfail]) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error1]) + RSEQ_ASM_DEFINE_EXIT_POINT(1f, %l[error2]) +#endif + "str %[src], %[rseq_scratch0]\n\t" + "str %[dst], %[rseq_scratch1]\n\t" + "str %[len], %[rseq_scratch2]\n\t" + /* Start rseq by storing table entry pointer into rseq_cs. */ + RSEQ_ASM_STORE_RSEQ_CS(1, 3f, rseq_cs) + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f) + RSEQ_INJECT_ASM(3) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne 5f\n\t" + RSEQ_INJECT_ASM(4) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 6f) + "ldr r0, %[v]\n\t" + "cmp %[expect], r0\n\t" + "bne 7f\n\t" +#endif + /* try memcpy */ + "cmp %[len], #0\n\t" \ + "beq 333f\n\t" \ + "222:\n\t" \ + "ldrb %%r0, [%[src]]\n\t" \ + "strb %%r0, [%[dst]]\n\t" \ + "adds %[src], #1\n\t" \ + "adds %[dst], #1\n\t" \ + "subs %[len], #1\n\t" \ + "bne 222b\n\t" \ + "333:\n\t" \ + RSEQ_INJECT_ASM(5) + "dmb\n\t" /* full mb provides store-release */ + /* final store */ + "str %[newv], %[v]\n\t" + "2:\n\t" + RSEQ_INJECT_ASM(6) + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t" + "b 8f\n\t" + RSEQ_ASM_DEFINE_ABORT(3, 4, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + abort, 1b, 2b, 4f) + RSEQ_ASM_DEFINE_CMPFAIL(5, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + cmpfail) +#ifdef RSEQ_COMPARE_TWICE + RSEQ_ASM_DEFINE_CMPFAIL(6, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + error1) + RSEQ_ASM_DEFINE_CMPFAIL(7, + /* teardown */ + "ldr %[len], %[rseq_scratch2]\n\t" + "ldr %[dst], %[rseq_scratch1]\n\t" + "ldr %[src], %[rseq_scratch0]\n\t", + error2) +#endif + "8:\n\t" + : /* gcc asm goto does not allow outputs */ + : [cpu_id] "r" (cpu), + [current_cpu_id] "m" (rseq_get_abi()->cpu_id), + [rseq_cs] "m" (rseq_get_abi()->rseq_cs.arch.ptr), + /* final store input */ + [v] "m" (*v), + [expect] "r" (expect), + [newv] "r" (newv), + /* try memcpy input */ + [dst] "r" (dst), + [src] "r" (src), + [len] "r" (len), + [rseq_scratch0] "m" (rseq_scratch[0]), + [rseq_scratch1] "m" (rseq_scratch[1]), + [rseq_scratch2] "m" (rseq_scratch[2]) + RSEQ_INJECT_INPUT + : "r0", "memory", "cc" + RSEQ_INJECT_CLOBBER + : abort, cmpfail +#ifdef RSEQ_COMPARE_TWICE + , error1, error2 +#endif + ); + rseq_after_asm_goto(); + return 0; +abort: + rseq_after_asm_goto(); + RSEQ_INJECT_FAILED + return -1; +cmpfail: + rseq_after_asm_goto(); + return 1; +#ifdef RSEQ_COMPARE_TWICE +error1: + rseq_after_asm_goto(); + rseq_bug("cpu_id comparison failed"); +error2: + rseq_after_asm_goto(); + rseq_bug("expected value comparison failed"); +#endif +} + +#endif /* !RSEQ_SKIP_FASTPATH */ |