f6a12a7d0b
futex_atomic_cmpxchg_inatomic exchanged if the values were unequal rather than equal. This caused incorrect behavior of robust futexes. Signed-off-by: Kirk Meyer <kirk.meyer@sencore.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com>
129 lines
2.8 KiB
C
129 lines
2.8 KiB
C
#ifndef _ASM_MICROBLAZE_FUTEX_H
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#define _ASM_MICROBLAZE_FUTEX_H
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#ifdef __KERNEL__
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#include <linux/futex.h>
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#include <linux/uaccess.h>
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#include <asm/errno.h>
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#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
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({ \
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__asm__ __volatile__ ( \
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"1: lwx %0, %2, r0; " \
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insn \
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"2: swx %1, %2, r0; \
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addic %1, r0, 0; \
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bnei %1, 1b; \
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3: \
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.section .fixup,\"ax\"; \
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4: brid 3b; \
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addik %1, r0, %3; \
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.previous; \
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.section __ex_table,\"a\"; \
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.word 1b,4b,2b,4b; \
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.previous;" \
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: "=&r" (oldval), "=&r" (ret) \
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: "r" (uaddr), "i" (-EFAULT), "r" (oparg) \
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); \
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})
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static inline int
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futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
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{
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int op = (encoded_op >> 28) & 7;
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int cmp = (encoded_op >> 24) & 15;
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int oparg = (encoded_op << 8) >> 20;
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int cmparg = (encoded_op << 20) >> 20;
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int oldval = 0, ret;
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if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
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oparg = 1 << oparg;
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if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
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return -EFAULT;
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pagefault_disable();
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switch (op) {
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case FUTEX_OP_SET:
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__futex_atomic_op("or %1,%4,%4;", ret, oldval, uaddr, oparg);
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break;
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case FUTEX_OP_ADD:
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__futex_atomic_op("add %1,%0,%4;", ret, oldval, uaddr, oparg);
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break;
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case FUTEX_OP_OR:
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__futex_atomic_op("or %1,%0,%4;", ret, oldval, uaddr, oparg);
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break;
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case FUTEX_OP_ANDN:
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__futex_atomic_op("andn %1,%0,%4;", ret, oldval, uaddr, oparg);
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break;
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case FUTEX_OP_XOR:
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__futex_atomic_op("xor %1,%0,%4;", ret, oldval, uaddr, oparg);
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break;
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default:
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ret = -ENOSYS;
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}
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pagefault_enable();
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if (!ret) {
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switch (cmp) {
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case FUTEX_OP_CMP_EQ:
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ret = (oldval == cmparg);
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break;
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case FUTEX_OP_CMP_NE:
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ret = (oldval != cmparg);
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break;
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case FUTEX_OP_CMP_LT:
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ret = (oldval < cmparg);
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break;
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case FUTEX_OP_CMP_GE:
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ret = (oldval >= cmparg);
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break;
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case FUTEX_OP_CMP_LE:
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ret = (oldval <= cmparg);
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break;
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case FUTEX_OP_CMP_GT:
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ret = (oldval > cmparg);
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break;
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default:
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ret = -ENOSYS;
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}
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}
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return ret;
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}
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static inline int
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futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
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u32 oldval, u32 newval)
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{
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int ret = 0, cmp;
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u32 prev;
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if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
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return -EFAULT;
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__asm__ __volatile__ ("1: lwx %1, %3, r0; \
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cmp %2, %1, %4; \
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bnei %2, 3f; \
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2: swx %5, %3, r0; \
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addic %2, r0, 0; \
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bnei %2, 1b; \
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3: \
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.section .fixup,\"ax\"; \
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4: brid 3b; \
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addik %0, r0, %6; \
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.previous; \
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.section __ex_table,\"a\"; \
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.word 1b,4b,2b,4b; \
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.previous;" \
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: "+r" (ret), "=&r" (prev), "=&r"(cmp) \
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: "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT));
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*uval = prev;
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return ret;
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}
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#endif /* __KERNEL__ */
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#endif
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