From 06fbac8e8971f2fa526e189304dd95ee62f39dbe Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Fri, 9 Nov 2018 19:32:06 -0800 Subject: [PATCH] xtensa: implement task_user_regset_view - define struct user_pt_regs in the arch/xtensa/include/uapi/asm/ptrace.h with the same layout as xtensa_gregset_t; make xtensa_gregset_t a typedef; - define REGSET_GPR regset, implement register get and set functions; - define task_user_regset_view function and expose REGSET_GPR. Signed-off-by: Max Filippov --- arch/xtensa/include/asm/elf.h | 14 +-- arch/xtensa/include/uapi/asm/ptrace.h | 18 +++ arch/xtensa/kernel/ptrace.c | 175 ++++++++++++++++---------- 3 files changed, 128 insertions(+), 79 deletions(-) diff --git a/arch/xtensa/include/asm/elf.h b/arch/xtensa/include/asm/elf.h index f3291b110a0d..c30c73eea267 100644 --- a/arch/xtensa/include/asm/elf.h +++ b/arch/xtensa/include/asm/elf.h @@ -75,19 +75,7 @@ typedef unsigned long elf_greg_t; -typedef struct { - elf_greg_t pc; - elf_greg_t ps; - elf_greg_t lbeg; - elf_greg_t lend; - elf_greg_t lcount; - elf_greg_t sar; - elf_greg_t windowstart; - elf_greg_t windowbase; - elf_greg_t threadptr; - elf_greg_t reserved[7+48]; - elf_greg_t a[64]; -} xtensa_gregset_t; +typedef struct user_pt_regs xtensa_gregset_t; #define ELF_NGREG (sizeof(xtensa_gregset_t) / sizeof(elf_greg_t)) diff --git a/arch/xtensa/include/uapi/asm/ptrace.h b/arch/xtensa/include/uapi/asm/ptrace.h index a10b42963703..2ec0f9100a06 100644 --- a/arch/xtensa/include/uapi/asm/ptrace.h +++ b/arch/xtensa/include/uapi/asm/ptrace.h @@ -12,6 +12,8 @@ #ifndef _UAPI_XTENSA_PTRACE_H #define _UAPI_XTENSA_PTRACE_H +#include + /* Registers used by strace */ #define REG_A_BASE 0x0000 @@ -36,5 +38,21 @@ #define PTRACE_GETHBPREGS 20 #define PTRACE_SETHBPREGS 21 +#ifndef __ASSEMBLY__ +struct user_pt_regs { + __u32 pc; + __u32 ps; + __u32 lbeg; + __u32 lend; + __u32 lcount; + __u32 sar; + __u32 windowstart; + __u32 windowbase; + __u32 threadptr; + __u32 reserved[7 + 48]; + __u32 a[64]; +}; + +#endif #endif /* _UAPI_XTENSA_PTRACE_H */ diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c index f73a6a71323e..ce751b1af7b3 100644 --- a/arch/xtensa/kernel/ptrace.c +++ b/arch/xtensa/kernel/ptrace.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -32,6 +33,110 @@ #include #include +static int gpr_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user *ubuf) +{ + struct pt_regs *regs = task_pt_regs(target); + struct user_pt_regs newregs = { + .pc = regs->pc, + .ps = regs->ps & ~(1 << PS_EXCM_BIT), + .lbeg = regs->lbeg, + .lend = regs->lend, + .lcount = regs->lcount, + .sar = regs->sar, + .threadptr = regs->threadptr, + .windowbase = regs->windowbase, + .windowstart = regs->windowstart, + }; + + memcpy(newregs.a, + regs->areg + XCHAL_NUM_AREGS - regs->windowbase * 4, + regs->windowbase * 16); + memcpy(newregs.a + regs->windowbase * 4, + regs->areg, + (WSBITS - regs->windowbase) * 16); + + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, + &newregs, 0, -1); +} + +static int gpr_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + int ret; + struct user_pt_regs newregs = {0}; + struct pt_regs *regs; + const u32 ps_mask = PS_CALLINC_MASK | PS_OWB_MASK; + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newregs, 0, -1); + if (ret) + return ret; + + if (newregs.windowbase >= XCHAL_NUM_AREGS / 4) + return -EINVAL; + + regs = task_pt_regs(target); + regs->pc = newregs.pc; + regs->ps = (regs->ps & ~ps_mask) | (newregs.ps & ps_mask); + regs->lbeg = newregs.lbeg; + regs->lend = newregs.lend; + regs->lcount = newregs.lcount; + regs->sar = newregs.sar; + regs->threadptr = newregs.threadptr; + + if (newregs.windowbase != regs->windowbase || + newregs.windowstart != regs->windowstart) { + u32 rotws, wmask; + + rotws = (((newregs.windowstart | + (newregs.windowstart << WSBITS)) >> + newregs.windowbase) & + ((1 << WSBITS) - 1)) & ~1; + wmask = ((rotws ? WSBITS + 1 - ffs(rotws) : 0) << 4) | + (rotws & 0xF) | 1; + regs->windowbase = newregs.windowbase; + regs->windowstart = newregs.windowstart; + regs->wmask = wmask; + } + + memcpy(regs->areg + XCHAL_NUM_AREGS - newregs.windowbase * 4, + newregs.a, newregs.windowbase * 16); + memcpy(regs->areg, newregs.a + newregs.windowbase * 4, + (WSBITS - newregs.windowbase) * 16); + + return 0; +} + +enum xtensa_regset { + REGSET_GPR, +}; + +static const struct user_regset xtensa_regsets[] = { + [REGSET_GPR] = { + .core_note_type = NT_PRSTATUS, + .n = sizeof(struct user_pt_regs) / sizeof(u32), + .size = sizeof(u32), + .align = sizeof(u32), + .get = gpr_get, + .set = gpr_set + }, +}; + +static const struct user_regset_view user_xtensa_view = { + .name = "xtensa", + .e_machine = EM_XTENSA, + .regsets = xtensa_regsets, + .n = ARRAY_SIZE(xtensa_regsets) +}; + +const struct user_regset_view *task_user_regset_view(struct task_struct *task) +{ + return &user_xtensa_view; +} void user_enable_single_step(struct task_struct *child) { @@ -54,76 +159,14 @@ void ptrace_disable(struct task_struct *child) static int ptrace_getregs(struct task_struct *child, void __user *uregs) { - struct pt_regs *regs = task_pt_regs(child); - xtensa_gregset_t __user *gregset = uregs; - unsigned long wb = regs->windowbase; - int i; - - if (!access_ok(VERIFY_WRITE, uregs, sizeof(xtensa_gregset_t))) - return -EIO; - - __put_user(regs->pc, &gregset->pc); - __put_user(regs->ps & ~(1 << PS_EXCM_BIT), &gregset->ps); - __put_user(regs->lbeg, &gregset->lbeg); - __put_user(regs->lend, &gregset->lend); - __put_user(regs->lcount, &gregset->lcount); - __put_user(regs->windowstart, &gregset->windowstart); - __put_user(regs->windowbase, &gregset->windowbase); - __put_user(regs->threadptr, &gregset->threadptr); - - for (i = 0; i < XCHAL_NUM_AREGS; i++) - __put_user(regs->areg[i], - gregset->a + ((wb * 4 + i) % XCHAL_NUM_AREGS)); - - return 0; + return copy_regset_to_user(child, &user_xtensa_view, REGSET_GPR, + 0, sizeof(xtensa_gregset_t), uregs); } static int ptrace_setregs(struct task_struct *child, void __user *uregs) { - struct pt_regs *regs = task_pt_regs(child); - xtensa_gregset_t *gregset = uregs; - const unsigned long ps_mask = PS_CALLINC_MASK | PS_OWB_MASK; - unsigned long ps; - unsigned long wb, ws; - - if (!access_ok(VERIFY_WRITE, uregs, sizeof(xtensa_gregset_t))) - return -EIO; - - __get_user(regs->pc, &gregset->pc); - __get_user(ps, &gregset->ps); - __get_user(regs->lbeg, &gregset->lbeg); - __get_user(regs->lend, &gregset->lend); - __get_user(regs->lcount, &gregset->lcount); - __get_user(ws, &gregset->windowstart); - __get_user(wb, &gregset->windowbase); - __get_user(regs->threadptr, &gregset->threadptr); - - regs->ps = (regs->ps & ~ps_mask) | (ps & ps_mask) | (1 << PS_EXCM_BIT); - - if (wb >= XCHAL_NUM_AREGS / 4) - return -EFAULT; - - if (wb != regs->windowbase || ws != regs->windowstart) { - unsigned long rotws, wmask; - - rotws = (((ws | (ws << WSBITS)) >> wb) & - ((1 << WSBITS) - 1)) & ~1; - wmask = ((rotws ? WSBITS + 1 - ffs(rotws) : 0) << 4) | - (rotws & 0xF) | 1; - regs->windowbase = wb; - regs->windowstart = ws; - regs->wmask = wmask; - } - - if (wb != 0 && __copy_from_user(regs->areg + XCHAL_NUM_AREGS - wb * 4, - gregset->a, wb * 16)) - return -EFAULT; - - if (__copy_from_user(regs->areg, gregset->a + wb * 4, - (WSBITS - wb) * 16)) - return -EFAULT; - - return 0; + return copy_regset_from_user(child, &user_xtensa_view, REGSET_GPR, + 0, sizeof(xtensa_gregset_t), uregs); }