From: pbrook Date: Sun, 28 Jan 2007 03:10:55 +0000 (+0000) Subject: GDB hosted syscalls. X-Git-Tag: release_0_9_0~38 X-Git-Url: https://git.proxmox.com/?p=qemu.git;a=commitdiff_plain;h=a2d1ebaf890da03de850812cc8dbec2d56efb4e8 GDB hosted syscalls. git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@2364 c046a42c-6fe2-441c-8c8c-71466251a162 --- diff --git a/arm-semi.c b/arm-semi.c index 4254cba84..4ddbc73c2 100644 --- a/arm-semi.c +++ b/arm-semi.c @@ -61,7 +61,30 @@ #define O_BINARY 0 #endif -int open_modeflags[12] = { +#define GDB_O_RDONLY 0x000 +#define GDB_O_WRONLY 0x001 +#define GDB_O_RDWR 0x002 +#define GDB_O_APPEND 0x008 +#define GDB_O_CREAT 0x200 +#define GDB_O_TRUNC 0x400 +#define GDB_O_BINARY 0 + +static int gdb_open_modeflags[12] = { + GDB_O_RDONLY, + GDB_O_RDONLY | GDB_O_BINARY, + GDB_O_RDWR, + GDB_O_RDWR | GDB_O_BINARY, + GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC, + GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY, + GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC, + GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY, + GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND, + GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY, + GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND, + GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY +}; + +static int open_modeflags[12] = { O_RDONLY, O_RDONLY | O_BINARY, O_RDWR, @@ -142,6 +165,35 @@ static void softmmu_unlock_user(CPUState *env, void *p, target_ulong addr, #define unlock_user(s, args, len) softmmu_unlock_user(env, s, args, len) #endif +static target_ulong arm_semi_syscall_len; + +static void arm_semi_cb(CPUState *env, target_ulong ret, target_ulong err) +{ +#ifdef CONFIG_USER_ONLY + TaskState *ts = env->opaque; +#endif + if (ret == (target_ulong)-1) { +#ifdef CONFIG_USER_ONLY + ts->swi_errno = err; +#endif + env->regs[0] = ret; + } else { + /* Fixup syscalls that use nonstardard return conventions. */ + switch (env->regs[0]) { + case SYS_WRITE: + case SYS_READ: + env->regs[0] = arm_semi_syscall_len - ret; + break; + case SYS_SEEK: + env->regs[0] = 0; + break; + default: + env->regs[0] = ret; + break; + } + } +} + #define ARG(n) tget32(args + (n) * 4) #define SET_ARG(n, val) tput32(args + (n) * 4,val) uint32_t do_arm_semihosting(CPUState *env) @@ -170,52 +222,99 @@ uint32_t do_arm_semihosting(CPUState *env) else return STDOUT_FILENO; } - ret = set_swi_errno(ts, open(s, open_modeflags[ARG(1)], 0644)); + if (use_gdb_syscalls()) { + gdb_do_syscall(arm_semi_cb, "open,%s,%x,1a4", ARG(0), (int)ARG(2), + gdb_open_modeflags[ARG(1)]); + return env->regs[0]; + } else { + ret = set_swi_errno(ts, open(s, open_modeflags[ARG(1)], 0644)); + } unlock_user(s, ARG(0), 0); return ret; case SYS_CLOSE: - return set_swi_errno(ts, close(ARG(0))); + if (use_gdb_syscalls()) { + gdb_do_syscall(arm_semi_cb, "close,%x", ARG(0)); + return env->regs[0]; + } else { + return set_swi_errno(ts, close(ARG(0))); + } case SYS_WRITEC: { char c = tget8(args); /* Write to debug console. stderr is near enough. */ - return write(STDERR_FILENO, &c, 1); + if (use_gdb_syscalls()) { + gdb_do_syscall(arm_semi_cb, "write,2,%x,1", args); + return env->regs[0]; + } else { + return write(STDERR_FILENO, &c, 1); + } } case SYS_WRITE0: s = lock_user_string(args); - ret = write(STDERR_FILENO, s, strlen(s)); + len = strlen(s); + if (use_gdb_syscalls()) { + gdb_do_syscall(arm_semi_cb, "write,2,%x,%x\n", args, len); + ret = env->regs[0]; + } else { + ret = write(STDERR_FILENO, s, len); + } unlock_user(s, args, 0); return ret; case SYS_WRITE: len = ARG(2); - s = lock_user(ARG(1), len, 1); - ret = set_swi_errno(ts, write(ARG(0), s, len)); - unlock_user(s, ARG(1), 0); - if (ret == (uint32_t)-1) - return -1; - return ARG(2) - ret; + if (use_gdb_syscalls()) { + arm_semi_syscall_len = len; + gdb_do_syscall(arm_semi_cb, "write,%x,%x,%x", ARG(0), ARG(1), len); + return env->regs[0]; + } else { + s = lock_user(ARG(1), len, 1); + ret = set_swi_errno(ts, write(ARG(0), s, len)); + unlock_user(s, ARG(1), 0); + if (ret == (uint32_t)-1) + return -1; + return len - ret; + } case SYS_READ: len = ARG(2); - s = lock_user(ARG(1), len, 0); - do - ret = set_swi_errno(ts, read(ARG(0), s, len)); - while (ret == -1 && errno == EINTR); - unlock_user(s, ARG(1), len); - if (ret == (uint32_t)-1) - return -1; - return ARG(2) - ret; + if (use_gdb_syscalls()) { + arm_semi_syscall_len = len; + gdb_do_syscall(arm_semi_cb, "read,%x,%x,%x", ARG(0), ARG(1), len); + return env->regs[0]; + } else { + s = lock_user(ARG(1), len, 0); + do + ret = set_swi_errno(ts, read(ARG(0), s, len)); + while (ret == -1 && errno == EINTR); + unlock_user(s, ARG(1), len); + if (ret == (uint32_t)-1) + return -1; + return len - ret; + } case SYS_READC: /* XXX: Read from debug cosole. Not implemented. */ return 0; case SYS_ISTTY: - return isatty(ARG(0)); + if (use_gdb_syscalls()) { + gdb_do_syscall(arm_semi_cb, "isatty,%x", ARG(0)); + return env->regs[0]; + } else { + return isatty(ARG(0)); + } case SYS_SEEK: - ret = set_swi_errno(ts, lseek(ARG(0), ARG(1), SEEK_SET)); - if (ret == (uint32_t)-1) - return -1; - return 0; + if (use_gdb_syscalls()) { + gdb_do_syscall(arm_semi_cb, "fseek,%x,%x,0", ARG(0), ARG(1)); + return env->regs[0]; + } else { + ret = set_swi_errno(ts, lseek(ARG(0), ARG(1), SEEK_SET)); + if (ret == (uint32_t)-1) + return -1; + return 0; + } case SYS_FLEN: - { + if (use_gdb_syscalls()) { + /* TODO: Use stat syscall. */ + return -1; + } else { struct stat buf; ret = set_swi_errno(ts, fstat(ARG(0), &buf)); if (ret == (uint32_t)-1) @@ -226,12 +325,21 @@ uint32_t do_arm_semihosting(CPUState *env) /* XXX: Not implemented. */ return -1; case SYS_REMOVE: - s = lock_user_string(ARG(0)); - ret = set_swi_errno(ts, remove(s)); - unlock_user(s, ARG(0), 0); + if (use_gdb_syscalls()) { + gdb_do_syscall(arm_semi_cb, "unlink,%s", ARG(0), (int)ARG(1)); + ret = env->regs[0]; + } else { + s = lock_user_string(ARG(0)); + ret = set_swi_errno(ts, remove(s)); + unlock_user(s, ARG(0), 0); + } return ret; case SYS_RENAME: - { + if (use_gdb_syscalls()) { + gdb_do_syscall(arm_semi_cb, "rename,%s,%s", + ARG(0), (int)ARG(1), ARG(2), (int)ARG(3)); + return env->regs[0]; + } else { char *s2; s = lock_user_string(ARG(0)); s2 = lock_user_string(ARG(2)); @@ -245,9 +353,14 @@ uint32_t do_arm_semihosting(CPUState *env) case SYS_TIME: return set_swi_errno(ts, time(NULL)); case SYS_SYSTEM: - s = lock_user_string(ARG(0)); - ret = set_swi_errno(ts, system(s)); - unlock_user(s, ARG(0), 0); + if (use_gdb_syscalls()) { + gdb_do_syscall(arm_semi_cb, "system,%s", ARG(0), (int)ARG(1)); + return env->regs[0]; + } else { + s = lock_user_string(ARG(0)); + ret = set_swi_errno(ts, system(s)); + unlock_user(s, ARG(0), 0); + } case SYS_ERRNO: #ifdef CONFIG_USER_ONLY return ts->swi_errno; diff --git a/gdbstub.c b/gdbstub.c index dd7fe42aa..a26c12ca6 100644 --- a/gdbstub.c +++ b/gdbstub.c @@ -52,6 +52,7 @@ enum RSState { RS_GETLINE, RS_CHKSUM1, RS_CHKSUM2, + RS_SYSCALL, }; typedef struct GDBState { CPUState *env; /* current CPU */ @@ -96,6 +97,27 @@ static int get_char(GDBState *s) } #endif +/* GDB stub state for use by semihosting syscalls. */ +static GDBState *gdb_syscall_state; +static gdb_syscall_complete_cb gdb_current_syscall_cb; + +enum { + GDB_SYS_UNKNOWN, + GDB_SYS_ENABLED, + GDB_SYS_DISABLED, +} gdb_syscall_mode; + +/* If gdb is connected when the first semihosting syscall occurs then use + remote gdb syscalls. Otherwise use native file IO. */ +int use_gdb_syscalls(void) +{ + if (gdb_syscall_mode == GDB_SYS_UNKNOWN) { + gdb_syscall_mode = (gdb_syscall_state ? GDB_SYS_ENABLED + : GDB_SYS_DISABLED); + } + return gdb_syscall_mode == GDB_SYS_ENABLED; +} + static void put_buffer(GDBState *s, const uint8_t *buf, int len) { #ifdef CONFIG_USER_ONLY @@ -755,6 +777,34 @@ static int gdb_handle_packet(GDBState *s, CPUState *env, const char *line_buf) vm_start(); #endif return RS_IDLE; + case 'F': + { + target_ulong ret; + target_ulong err; + + ret = strtoull(p, (char **)&p, 16); + if (*p == ',') { + p++; + err = strtoull(p, (char **)&p, 16); + } else { + err = 0; + } + if (*p == ',') + p++; + type = *p; + if (gdb_current_syscall_cb) + gdb_current_syscall_cb(s->env, ret, err); + if (type == 'C') { + put_packet(s, "T02"); + } else { +#ifdef CONFIG_USER_ONLY + s->running_state = 1; +#else + vm_start(); +#endif + } + } + break; case 'g': reg_size = cpu_gdb_read_registers(env, mem_buf); memtohex(buf, mem_buf, reg_size); @@ -855,6 +905,9 @@ static void gdb_vm_stopped(void *opaque, int reason) char buf[256]; int ret; + if (s->state == RS_SYSCALL) + return; + /* disable single step if it was enable */ cpu_single_step(s->env, 0); @@ -871,6 +924,60 @@ static void gdb_vm_stopped(void *opaque, int reason) } #endif +/* Send a gdb syscall request. + This accepts limited printf-style format specifiers, specifically: + %x - target_ulong argument printed in hex. + %s - string pointer (target_ulong) and length (int) pair. */ +void gdb_do_syscall(gdb_syscall_complete_cb cb, char *fmt, ...) +{ + va_list va; + char buf[256]; + char *p; + target_ulong addr; + GDBState *s; + + s = gdb_syscall_state; + if (!s) + return; + gdb_current_syscall_cb = cb; + s->state = RS_SYSCALL; +#ifndef CONFIG_USER_ONLY + vm_stop(EXCP_DEBUG); +#endif + s->state = RS_IDLE; + va_start(va, fmt); + p = buf; + *(p++) = 'F'; + while (*fmt) { + if (*fmt == '%') { + fmt++; + switch (*fmt++) { + case 'x': + addr = va_arg(va, target_ulong); + p += sprintf(p, TARGET_FMT_lx, addr); + break; + case 's': + addr = va_arg(va, target_ulong); + p += sprintf(p, TARGET_FMT_lx "/%x", addr, va_arg(va, int)); + break; + default: + fprintf(stderr, "gdbstub: Bad syscall format string '%s'\n", + fmt - 1); + break; + } + } else { + *(p++) = *(fmt++); + } + } + va_end(va); + put_packet(s, buf); +#ifdef CONFIG_USER_ONLY + gdb_handlesig(s->env, 0); +#else + cpu_interrupt(s->env, CPU_INTERRUPT_EXIT); +#endif +} + static void gdb_read_byte(GDBState *s, int ch) { CPUState *env = s->env; @@ -942,6 +1049,8 @@ static void gdb_read_byte(GDBState *s, int ch) s->state = gdb_handle_packet(s, env, s->line_buf); } break; + default: + abort(); } } } @@ -1034,6 +1143,8 @@ static void gdb_accept(void *opaque) s->env = first_cpu; /* XXX: allow to change CPU */ s->fd = fd; + gdb_syscall_state = s; + fcntl(fd, F_SETFL, O_NONBLOCK); } @@ -1098,6 +1209,7 @@ static void gdb_chr_event(void *opaque, int event) switch (event) { case CHR_EVENT_RESET: vm_stop(EXCP_INTERRUPT); + gdb_syscall_state = opaque; break; default: break; diff --git a/gdbstub.h b/gdbstub.h index c9d5c6827..c5b52c2e2 100644 --- a/gdbstub.h +++ b/gdbstub.h @@ -3,6 +3,11 @@ #define DEFAULT_GDBSTUB_PORT 1234 +typedef void (*gdb_syscall_complete_cb)(CPUState *env, + target_ulong ret, target_ulong err); + +void gdb_do_syscall(gdb_syscall_complete_cb cb, char *fmt, ...); +int use_gdb_syscalls(void); #ifdef CONFIG_USER_ONLY int gdb_handlesig (CPUState *, int); void gdb_exit(CPUState *, int);