xemu/semihosting/arm-compat-semi.c

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/*
* Semihosting support for systems modeled on the Arm "Angel"
* semihosting syscalls design. This includes Arm and RISC-V processors
*
* Copyright (c) 2005, 2007 CodeSourcery.
* Copyright (c) 2019 Linaro
* Written by Paul Brook.
*
* Copyright © 2020 by Keith Packard <keithp@keithp.com>
* Adapted for systems other than ARM, including RISC-V, by Keith Packard
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*
* ARM Semihosting is documented in:
* Semihosting for AArch32 and AArch64 Release 2.0
* https://github.com/ARM-software/abi-aa/blob/main/semihosting/semihosting.rst
*
* RISC-V Semihosting is documented in:
* RISC-V Semihosting
* https://github.com/riscv/riscv-semihosting-spec/blob/main/riscv-semihosting-spec.adoc
*/
#include "qemu/osdep.h"
#include "qemu/timer.h"
#include "exec/gdbstub.h"
#include "semihosting/semihost.h"
#include "semihosting/console.h"
#include "semihosting/common-semi.h"
#include "semihosting/guestfd.h"
#include "semihosting/syscalls.h"
#ifdef CONFIG_USER_ONLY
#include "qemu.h"
semihosting: Change internal common-semi interfaces to use CPUState * This makes all of the internal interfaces architecture-independent and renames the internal functions to use the 'common_semi' prefix instead of 'arm' or 'arm_semi'. To do this, some new architecture-specific internal helper functions were created: static inline target_ulong common_semi_arg(CPUState *cs, int argno) Returns the argno'th semihosting argument, where argno can be either 0 or 1. static inline void common_semi_set_ret(CPUState *cs, target_ulong ret) Sets the semihosting return value. static inline bool common_semi_sys_exit_extended(CPUState *cs, int nr) This detects whether the specified semihosting call, which is either TARGET_SYS_EXIT or TARGET_SYS_EXIT_EXTENDED should be executed using the TARGET_SYS_EXIT_EXTENDED semantics. static inline target_ulong common_semi_rambase(CPUState *cs) Returns the base of RAM region used for heap and stack. This is used to construct plausible values for the SYS_HEAPINFO call. In addition, several existing functions have been changed to flag areas of code which are architecture specific: static target_ulong common_semi_flen_buf(CPUState *cs) Returns the current stack pointer minus 64, which is where a stat structure will be placed on the stack #define GET_ARG(n) This fetches arguments from the semihosting command's argument block. The address of this is available implicitly through the local 'args' variable. This is *mostly* architecture independent, but does depend on the current ABI's notion of the size of a 'long' parameter, which may need run-time checks (as it does on AARCH64) #define SET_ARG(n, val) This mirrors GET_ARG and stores data back into the argument block. Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20210107170717.2098982-4-keithp@keithp.com> Message-Id: <20210108224256.2321-15-alex.bennee@linaro.org>
2021-01-08 17:42:50 -05:00
#define COMMON_SEMI_HEAP_SIZE (128 * 1024 * 1024)
#else
#include "qemu/cutils.h"
#include "hw/loader.h"
#include "hw/boards.h"
#endif
#define TARGET_SYS_OPEN 0x01
#define TARGET_SYS_CLOSE 0x02
#define TARGET_SYS_WRITEC 0x03
#define TARGET_SYS_WRITE0 0x04
#define TARGET_SYS_WRITE 0x05
#define TARGET_SYS_READ 0x06
#define TARGET_SYS_READC 0x07
#define TARGET_SYS_ISERROR 0x08
#define TARGET_SYS_ISTTY 0x09
#define TARGET_SYS_SEEK 0x0a
#define TARGET_SYS_FLEN 0x0c
#define TARGET_SYS_TMPNAM 0x0d
#define TARGET_SYS_REMOVE 0x0e
#define TARGET_SYS_RENAME 0x0f
#define TARGET_SYS_CLOCK 0x10
#define TARGET_SYS_TIME 0x11
#define TARGET_SYS_SYSTEM 0x12
#define TARGET_SYS_ERRNO 0x13
#define TARGET_SYS_GET_CMDLINE 0x15
#define TARGET_SYS_HEAPINFO 0x16
#define TARGET_SYS_EXIT 0x18
#define TARGET_SYS_SYNCCACHE 0x19
#define TARGET_SYS_EXIT_EXTENDED 0x20
#define TARGET_SYS_ELAPSED 0x30
#define TARGET_SYS_TICKFREQ 0x31
/* ADP_Stopped_ApplicationExit is used for exit(0),
* anything else is implemented as exit(1) */
#define ADP_Stopped_ApplicationExit (0x20026)
#ifndef O_BINARY
#define O_BINARY 0
#endif
static int gdb_open_modeflags[12] = {
GDB_O_RDONLY,
GDB_O_RDONLY,
GDB_O_RDWR,
GDB_O_RDWR,
GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC,
GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC,
GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC,
GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC,
GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND,
GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND,
GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND,
GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND,
};
#ifndef CONFIG_USER_ONLY
/**
* common_semi_find_bases: find information about ram and heap base
*
* This function attempts to provide meaningful numbers for RAM and
* HEAP base addresses. The rambase is simply the lowest addressable
* RAM position. For the heapbase we ask the loader to scan the
* address space and the largest available gap by querying the "ROM"
* regions.
*
* Returns: a structure with the numbers we need.
*/
typedef struct LayoutInfo {
target_ulong rambase;
size_t ramsize;
hwaddr heapbase;
hwaddr heaplimit;
} LayoutInfo;
static bool find_ram_cb(Int128 start, Int128 len, const MemoryRegion *mr,
hwaddr offset_in_region, void *opaque)
{
LayoutInfo *info = (LayoutInfo *) opaque;
uint64_t size = int128_get64(len);
if (!mr->ram || mr->readonly) {
return false;
}
if (size > info->ramsize) {
info->rambase = int128_get64(start);
info->ramsize = size;
}
/* search exhaustively for largest RAM */
return false;
}
static LayoutInfo common_semi_find_bases(CPUState *cs)
{
FlatView *fv;
LayoutInfo info = { 0, 0, 0, 0 };
RCU_READ_LOCK_GUARD();
fv = address_space_to_flatview(cs->as);
flatview_for_each_range(fv, find_ram_cb, &info);
/*
* If we have found the RAM lets iterate through the ROM blobs to
* work out the best place for the remainder of RAM and split it
* equally between stack and heap.
*/
if (info.rambase || info.ramsize > 0) {
RomGap gap = rom_find_largest_gap_between(info.rambase, info.ramsize);
info.heapbase = gap.base;
info.heaplimit = gap.base + gap.size;
}
return info;
}
#endif
#include "common-semi-target.h"
/*
* Read the input value from the argument block; fail the semihosting
* call if the memory read fails. Eventually we could use a generic
* CPUState helper function here.
* Note that GET_ARG() handles memory access errors by jumping to
* do_fault, so must be used as the first thing done in handling a
* semihosting call, to avoid accidentally leaking allocated resources.
* SET_ARG(), since it unavoidably happens late, instead returns an
* error indication (0 on success, non-0 for error) which the caller
* should check.
*/
#define GET_ARG(n) do { \
if (is_64bit_semihosting(env)) { \
if (get_user_u64(arg ## n, args + (n) * 8)) { \
goto do_fault; \
} \
} else { \
if (get_user_u32(arg ## n, args + (n) * 4)) { \
goto do_fault; \
} \
} \
} while (0)
#define SET_ARG(n, val) \
(is_64bit_semihosting(env) ? \
put_user_u64(val, args + (n) * 8) : \
put_user_u32(val, args + (n) * 4))
/*
* The semihosting API has no concept of its errno being thread-safe,
* as the API design predates SMP CPUs and was intended as a simple
* real-hardware set of debug functionality. For QEMU, we make the
* errno be per-thread in linux-user mode; in softmmu it is a simple
* global, and we assume that the guest takes care of avoiding any races.
*/
#ifndef CONFIG_USER_ONLY
static target_ulong syscall_err;
#include "semihosting/softmmu-uaccess.h"
#endif
semihosting: Change internal common-semi interfaces to use CPUState * This makes all of the internal interfaces architecture-independent and renames the internal functions to use the 'common_semi' prefix instead of 'arm' or 'arm_semi'. To do this, some new architecture-specific internal helper functions were created: static inline target_ulong common_semi_arg(CPUState *cs, int argno) Returns the argno'th semihosting argument, where argno can be either 0 or 1. static inline void common_semi_set_ret(CPUState *cs, target_ulong ret) Sets the semihosting return value. static inline bool common_semi_sys_exit_extended(CPUState *cs, int nr) This detects whether the specified semihosting call, which is either TARGET_SYS_EXIT or TARGET_SYS_EXIT_EXTENDED should be executed using the TARGET_SYS_EXIT_EXTENDED semantics. static inline target_ulong common_semi_rambase(CPUState *cs) Returns the base of RAM region used for heap and stack. This is used to construct plausible values for the SYS_HEAPINFO call. In addition, several existing functions have been changed to flag areas of code which are architecture specific: static target_ulong common_semi_flen_buf(CPUState *cs) Returns the current stack pointer minus 64, which is where a stat structure will be placed on the stack #define GET_ARG(n) This fetches arguments from the semihosting command's argument block. The address of this is available implicitly through the local 'args' variable. This is *mostly* architecture independent, but does depend on the current ABI's notion of the size of a 'long' parameter, which may need run-time checks (as it does on AARCH64) #define SET_ARG(n, val) This mirrors GET_ARG and stores data back into the argument block. Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20210107170717.2098982-4-keithp@keithp.com> Message-Id: <20210108224256.2321-15-alex.bennee@linaro.org>
2021-01-08 17:42:50 -05:00
static inline uint32_t get_swi_errno(CPUState *cs)
{
#ifdef CONFIG_USER_ONLY
TaskState *ts = cs->opaque;
return ts->swi_errno;
#else
return syscall_err;
#endif
}
static void common_semi_cb(CPUState *cs, uint64_t ret, int err)
{
if (err) {
#ifdef CONFIG_USER_ONLY
TaskState *ts = cs->opaque;
ts->swi_errno = err;
#else
syscall_err = err;
#endif
}
common_semi_set_ret(cs, ret);
}
/*
* Use 0xdeadbeef as the return value when there isn't a defined
* return value for the call.
*/
static void common_semi_dead_cb(CPUState *cs, uint64_t ret, int err)
{
common_semi_set_ret(cs, 0xdeadbeef);
}
/*
* SYS_READ and SYS_WRITE always return the number of bytes not read/written.
* There is no error condition, other than returning the original length.
*/
static void common_semi_rw_cb(CPUState *cs, uint64_t ret, int err)
{
/* Recover the original length from the third argument. */
CPUArchState *env G_GNUC_UNUSED = cs->env_ptr;
target_ulong args = common_semi_arg(cs, 1);
target_ulong arg2;
GET_ARG(2);
if (err) {
do_fault:
ret = 0; /* error: no bytes transmitted */
}
common_semi_set_ret(cs, arg2 - ret);
}
/*
* Convert from Posix ret+errno to Arm SYS_ISTTY return values.
* With gdbstub, err is only ever set for protocol errors to EIO.
*/
static void common_semi_istty_cb(CPUState *cs, uint64_t ret, int err)
{
if (err) {
ret = (err == ENOTTY ? 0 : -1);
}
common_semi_cb(cs, ret, err);
}
/*
* SYS_SEEK returns 0 on success, not the resulting offset.
*/
static void common_semi_seek_cb(CPUState *cs, uint64_t ret, int err)
{
if (!err) {
ret = 0;
}
common_semi_cb(cs, ret, err);
}
/*
* Return an address in target memory of 64 bytes where the remote
* gdb should write its stat struct. (The format of this structure
* is defined by GDB's remote protocol and is not target-specific.)
* We put this on the guest's stack just below SP.
*/
semihosting: Change internal common-semi interfaces to use CPUState * This makes all of the internal interfaces architecture-independent and renames the internal functions to use the 'common_semi' prefix instead of 'arm' or 'arm_semi'. To do this, some new architecture-specific internal helper functions were created: static inline target_ulong common_semi_arg(CPUState *cs, int argno) Returns the argno'th semihosting argument, where argno can be either 0 or 1. static inline void common_semi_set_ret(CPUState *cs, target_ulong ret) Sets the semihosting return value. static inline bool common_semi_sys_exit_extended(CPUState *cs, int nr) This detects whether the specified semihosting call, which is either TARGET_SYS_EXIT or TARGET_SYS_EXIT_EXTENDED should be executed using the TARGET_SYS_EXIT_EXTENDED semantics. static inline target_ulong common_semi_rambase(CPUState *cs) Returns the base of RAM region used for heap and stack. This is used to construct plausible values for the SYS_HEAPINFO call. In addition, several existing functions have been changed to flag areas of code which are architecture specific: static target_ulong common_semi_flen_buf(CPUState *cs) Returns the current stack pointer minus 64, which is where a stat structure will be placed on the stack #define GET_ARG(n) This fetches arguments from the semihosting command's argument block. The address of this is available implicitly through the local 'args' variable. This is *mostly* architecture independent, but does depend on the current ABI's notion of the size of a 'long' parameter, which may need run-time checks (as it does on AARCH64) #define SET_ARG(n, val) This mirrors GET_ARG and stores data back into the argument block. Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20210107170717.2098982-4-keithp@keithp.com> Message-Id: <20210108224256.2321-15-alex.bennee@linaro.org>
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static target_ulong common_semi_flen_buf(CPUState *cs)
{
target_ulong sp = common_semi_stack_bottom(cs);
return sp - 64;
}
semihosting: Change internal common-semi interfaces to use CPUState * This makes all of the internal interfaces architecture-independent and renames the internal functions to use the 'common_semi' prefix instead of 'arm' or 'arm_semi'. To do this, some new architecture-specific internal helper functions were created: static inline target_ulong common_semi_arg(CPUState *cs, int argno) Returns the argno'th semihosting argument, where argno can be either 0 or 1. static inline void common_semi_set_ret(CPUState *cs, target_ulong ret) Sets the semihosting return value. static inline bool common_semi_sys_exit_extended(CPUState *cs, int nr) This detects whether the specified semihosting call, which is either TARGET_SYS_EXIT or TARGET_SYS_EXIT_EXTENDED should be executed using the TARGET_SYS_EXIT_EXTENDED semantics. static inline target_ulong common_semi_rambase(CPUState *cs) Returns the base of RAM region used for heap and stack. This is used to construct plausible values for the SYS_HEAPINFO call. In addition, several existing functions have been changed to flag areas of code which are architecture specific: static target_ulong common_semi_flen_buf(CPUState *cs) Returns the current stack pointer minus 64, which is where a stat structure will be placed on the stack #define GET_ARG(n) This fetches arguments from the semihosting command's argument block. The address of this is available implicitly through the local 'args' variable. This is *mostly* architecture independent, but does depend on the current ABI's notion of the size of a 'long' parameter, which may need run-time checks (as it does on AARCH64) #define SET_ARG(n, val) This mirrors GET_ARG and stores data back into the argument block. Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20210107170717.2098982-4-keithp@keithp.com> Message-Id: <20210108224256.2321-15-alex.bennee@linaro.org>
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static void
common_semi_flen_fstat_cb(CPUState *cs, uint64_t ret, int err)
{
if (!err) {
/* The size is always stored in big-endian order, extract the value. */
uint64_t size;
if (cpu_memory_rw_debug(cs, common_semi_flen_buf(cs) +
offsetof(struct gdb_stat, gdb_st_size),
&size, 8, 0)) {
ret = -1, err = EFAULT;
} else {
size = be64_to_cpu(size);
if (ret != size) {
ret = -1, err = EOVERFLOW;
}
}
}
common_semi_cb(cs, ret, err);
}
static void
common_semi_readc_cb(CPUState *cs, uint64_t ret, int err)
{
if (!err) {
CPUArchState *env G_GNUC_UNUSED = cs->env_ptr;
uint8_t ch;
if (get_user_u8(ch, common_semi_stack_bottom(cs) - 1)) {
ret = -1, err = EFAULT;
} else {
ret = ch;
}
}
common_semi_cb(cs, ret, err);
}
#define SHFB_MAGIC_0 0x53
#define SHFB_MAGIC_1 0x48
#define SHFB_MAGIC_2 0x46
#define SHFB_MAGIC_3 0x42
/* Feature bits reportable in feature byte 0 */
#define SH_EXT_EXIT_EXTENDED (1 << 0)
#define SH_EXT_STDOUT_STDERR (1 << 1)
static const uint8_t featurefile_data[] = {
SHFB_MAGIC_0,
SHFB_MAGIC_1,
SHFB_MAGIC_2,
SHFB_MAGIC_3,
SH_EXT_EXIT_EXTENDED | SH_EXT_STDOUT_STDERR, /* Feature byte 0 */
};
/*
* Do a semihosting call.
*
* The specification always says that the "return register" either
* returns a specific value or is corrupted, so we don't need to
* report to our caller whether we are returning a value or trying to
* leave the register unchanged.
*/
void do_common_semihosting(CPUState *cs)
{
semihosting: Change internal common-semi interfaces to use CPUState * This makes all of the internal interfaces architecture-independent and renames the internal functions to use the 'common_semi' prefix instead of 'arm' or 'arm_semi'. To do this, some new architecture-specific internal helper functions were created: static inline target_ulong common_semi_arg(CPUState *cs, int argno) Returns the argno'th semihosting argument, where argno can be either 0 or 1. static inline void common_semi_set_ret(CPUState *cs, target_ulong ret) Sets the semihosting return value. static inline bool common_semi_sys_exit_extended(CPUState *cs, int nr) This detects whether the specified semihosting call, which is either TARGET_SYS_EXIT or TARGET_SYS_EXIT_EXTENDED should be executed using the TARGET_SYS_EXIT_EXTENDED semantics. static inline target_ulong common_semi_rambase(CPUState *cs) Returns the base of RAM region used for heap and stack. This is used to construct plausible values for the SYS_HEAPINFO call. In addition, several existing functions have been changed to flag areas of code which are architecture specific: static target_ulong common_semi_flen_buf(CPUState *cs) Returns the current stack pointer minus 64, which is where a stat structure will be placed on the stack #define GET_ARG(n) This fetches arguments from the semihosting command's argument block. The address of this is available implicitly through the local 'args' variable. This is *mostly* architecture independent, but does depend on the current ABI's notion of the size of a 'long' parameter, which may need run-time checks (as it does on AARCH64) #define SET_ARG(n, val) This mirrors GET_ARG and stores data back into the argument block. Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20210107170717.2098982-4-keithp@keithp.com> Message-Id: <20210108224256.2321-15-alex.bennee@linaro.org>
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CPUArchState *env = cs->env_ptr;
target_ulong args;
target_ulong arg0, arg1, arg2, arg3;
target_ulong ul_ret;
char * s;
int nr;
uint32_t ret;
int64_t elapsed;
semihosting: Change internal common-semi interfaces to use CPUState * This makes all of the internal interfaces architecture-independent and renames the internal functions to use the 'common_semi' prefix instead of 'arm' or 'arm_semi'. To do this, some new architecture-specific internal helper functions were created: static inline target_ulong common_semi_arg(CPUState *cs, int argno) Returns the argno'th semihosting argument, where argno can be either 0 or 1. static inline void common_semi_set_ret(CPUState *cs, target_ulong ret) Sets the semihosting return value. static inline bool common_semi_sys_exit_extended(CPUState *cs, int nr) This detects whether the specified semihosting call, which is either TARGET_SYS_EXIT or TARGET_SYS_EXIT_EXTENDED should be executed using the TARGET_SYS_EXIT_EXTENDED semantics. static inline target_ulong common_semi_rambase(CPUState *cs) Returns the base of RAM region used for heap and stack. This is used to construct plausible values for the SYS_HEAPINFO call. In addition, several existing functions have been changed to flag areas of code which are architecture specific: static target_ulong common_semi_flen_buf(CPUState *cs) Returns the current stack pointer minus 64, which is where a stat structure will be placed on the stack #define GET_ARG(n) This fetches arguments from the semihosting command's argument block. The address of this is available implicitly through the local 'args' variable. This is *mostly* architecture independent, but does depend on the current ABI's notion of the size of a 'long' parameter, which may need run-time checks (as it does on AARCH64) #define SET_ARG(n, val) This mirrors GET_ARG and stores data back into the argument block. Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20210107170717.2098982-4-keithp@keithp.com> Message-Id: <20210108224256.2321-15-alex.bennee@linaro.org>
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nr = common_semi_arg(cs, 0) & 0xffffffffU;
args = common_semi_arg(cs, 1);
switch (nr) {
case TARGET_SYS_OPEN:
target/arm/arm-semi: Make semihosting code hand out its own file descriptors Currently the Arm semihosting code returns the guest file descriptors (handles) which are simply the fd values from the host OS or the remote gdbstub. Part of the semihosting 2.0 specification requires that we implement special handling of opening a ":semihosting-features" filename. Guest fds which result from opening the special file won't correspond to host fds, so to ensure that we don't end up with duplicate fds we need to have QEMU code control the allocation of the fd values we give the guest. Add in an abstraction layer which lets us allocate new guest FD values, and translate from a guest FD value back to the host one. This also fixes an odd hole where a semihosting guest could use the semihosting API to read, write or close file descriptors that it had never allocated but which were being used by QEMU itself. (This isn't a security hole, because enabling semihosting permits the guest to do arbitrary file access to the whole host filesystem, and so should only be done if the guest is completely trusted.) Currently the only kind of guest fd is one which maps to a host fd, but in a following commit we will add one which maps to the :semihosting-features magic data. If the guest is migrated with an open semihosting file descriptor then subsequent attempts to use the fd will all fail; this is not a change from the previous situation (where the host fd being used on the source end would not be re-opened on the destination end). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20190916141544.17540-5-peter.maydell@linaro.org
2019-09-16 10:15:33 -04:00
{
int ret, err = 0;
int hostfd;
target/arm/arm-semi: Make semihosting code hand out its own file descriptors Currently the Arm semihosting code returns the guest file descriptors (handles) which are simply the fd values from the host OS or the remote gdbstub. Part of the semihosting 2.0 specification requires that we implement special handling of opening a ":semihosting-features" filename. Guest fds which result from opening the special file won't correspond to host fds, so to ensure that we don't end up with duplicate fds we need to have QEMU code control the allocation of the fd values we give the guest. Add in an abstraction layer which lets us allocate new guest FD values, and translate from a guest FD value back to the host one. This also fixes an odd hole where a semihosting guest could use the semihosting API to read, write or close file descriptors that it had never allocated but which were being used by QEMU itself. (This isn't a security hole, because enabling semihosting permits the guest to do arbitrary file access to the whole host filesystem, and so should only be done if the guest is completely trusted.) Currently the only kind of guest fd is one which maps to a host fd, but in a following commit we will add one which maps to the :semihosting-features magic data. If the guest is migrated with an open semihosting file descriptor then subsequent attempts to use the fd will all fail; this is not a change from the previous situation (where the host fd being used on the source end would not be re-opened on the destination end). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20190916141544.17540-5-peter.maydell@linaro.org
2019-09-16 10:15:33 -04:00
GET_ARG(0);
GET_ARG(1);
GET_ARG(2);
s = lock_user_string(arg0);
if (!s) {
goto do_fault;
}
if (arg1 >= 12) {
unlock_user(s, arg0, 0);
common_semi_cb(cs, -1, EINVAL);
break;
target/arm/arm-semi: Make semihosting code hand out its own file descriptors Currently the Arm semihosting code returns the guest file descriptors (handles) which are simply the fd values from the host OS or the remote gdbstub. Part of the semihosting 2.0 specification requires that we implement special handling of opening a ":semihosting-features" filename. Guest fds which result from opening the special file won't correspond to host fds, so to ensure that we don't end up with duplicate fds we need to have QEMU code control the allocation of the fd values we give the guest. Add in an abstraction layer which lets us allocate new guest FD values, and translate from a guest FD value back to the host one. This also fixes an odd hole where a semihosting guest could use the semihosting API to read, write or close file descriptors that it had never allocated but which were being used by QEMU itself. (This isn't a security hole, because enabling semihosting permits the guest to do arbitrary file access to the whole host filesystem, and so should only be done if the guest is completely trusted.) Currently the only kind of guest fd is one which maps to a host fd, but in a following commit we will add one which maps to the :semihosting-features magic data. If the guest is migrated with an open semihosting file descriptor then subsequent attempts to use the fd will all fail; this is not a change from the previous situation (where the host fd being used on the source end would not be re-opened on the destination end). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20190916141544.17540-5-peter.maydell@linaro.org
2019-09-16 10:15:33 -04:00
}
if (strcmp(s, ":tt") == 0) {
/*
* We implement SH_EXT_STDOUT_STDERR, so:
* open for read == stdin
* open for write == stdout
* open for append == stderr
*/
if (arg1 < 4) {
hostfd = STDIN_FILENO;
} else if (arg1 < 8) {
hostfd = STDOUT_FILENO;
} else {
hostfd = STDERR_FILENO;
}
ret = alloc_guestfd();
associate_guestfd(ret, hostfd);
} else if (strcmp(s, ":semihosting-features") == 0) {
/* We must fail opens for modes other than 0 ('r') or 1 ('rb') */
if (arg1 != 0 && arg1 != 1) {
ret = -1;
err = EACCES;
} else {
ret = alloc_guestfd();
staticfile_guestfd(ret, featurefile_data,
sizeof(featurefile_data));
}
} else {
unlock_user(s, arg0, 0);
semihost_sys_open(cs, common_semi_cb, arg0, arg2 + 1,
gdb_open_modeflags[arg1], 0644);
break;
}
unlock_user(s, arg0, 0);
common_semi_cb(cs, ret, err);
break;
target/arm/arm-semi: Make semihosting code hand out its own file descriptors Currently the Arm semihosting code returns the guest file descriptors (handles) which are simply the fd values from the host OS or the remote gdbstub. Part of the semihosting 2.0 specification requires that we implement special handling of opening a ":semihosting-features" filename. Guest fds which result from opening the special file won't correspond to host fds, so to ensure that we don't end up with duplicate fds we need to have QEMU code control the allocation of the fd values we give the guest. Add in an abstraction layer which lets us allocate new guest FD values, and translate from a guest FD value back to the host one. This also fixes an odd hole where a semihosting guest could use the semihosting API to read, write or close file descriptors that it had never allocated but which were being used by QEMU itself. (This isn't a security hole, because enabling semihosting permits the guest to do arbitrary file access to the whole host filesystem, and so should only be done if the guest is completely trusted.) Currently the only kind of guest fd is one which maps to a host fd, but in a following commit we will add one which maps to the :semihosting-features magic data. If the guest is migrated with an open semihosting file descriptor then subsequent attempts to use the fd will all fail; this is not a change from the previous situation (where the host fd being used on the source end would not be re-opened on the destination end). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20190916141544.17540-5-peter.maydell@linaro.org
2019-09-16 10:15:33 -04:00
}
case TARGET_SYS_CLOSE:
GET_ARG(0);
semihost_sys_close(cs, common_semi_cb, arg0);
break;
case TARGET_SYS_WRITEC:
/*
* FIXME: the byte to be written is in a target_ulong slot,
* which means this is wrong for a big-endian guest.
*/
semihost_sys_write_gf(cs, common_semi_dead_cb,
&console_out_gf, args, 1);
break;
case TARGET_SYS_WRITE0:
{
ssize_t len = target_strlen(args);
if (len < 0) {
common_semi_dead_cb(cs, -1, EFAULT);
} else {
semihost_sys_write_gf(cs, common_semi_dead_cb,
&console_out_gf, args, len);
}
}
break;
case TARGET_SYS_WRITE:
GET_ARG(0);
GET_ARG(1);
GET_ARG(2);
semihost_sys_write(cs, common_semi_rw_cb, arg0, arg1, arg2);
break;
target/arm/arm-semi: Make semihosting code hand out its own file descriptors Currently the Arm semihosting code returns the guest file descriptors (handles) which are simply the fd values from the host OS or the remote gdbstub. Part of the semihosting 2.0 specification requires that we implement special handling of opening a ":semihosting-features" filename. Guest fds which result from opening the special file won't correspond to host fds, so to ensure that we don't end up with duplicate fds we need to have QEMU code control the allocation of the fd values we give the guest. Add in an abstraction layer which lets us allocate new guest FD values, and translate from a guest FD value back to the host one. This also fixes an odd hole where a semihosting guest could use the semihosting API to read, write or close file descriptors that it had never allocated but which were being used by QEMU itself. (This isn't a security hole, because enabling semihosting permits the guest to do arbitrary file access to the whole host filesystem, and so should only be done if the guest is completely trusted.) Currently the only kind of guest fd is one which maps to a host fd, but in a following commit we will add one which maps to the :semihosting-features magic data. If the guest is migrated with an open semihosting file descriptor then subsequent attempts to use the fd will all fail; this is not a change from the previous situation (where the host fd being used on the source end would not be re-opened on the destination end). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20190916141544.17540-5-peter.maydell@linaro.org
2019-09-16 10:15:33 -04:00
case TARGET_SYS_READ:
GET_ARG(0);
GET_ARG(1);
GET_ARG(2);
semihost_sys_read(cs, common_semi_rw_cb, arg0, arg1, arg2);
break;
target/arm/arm-semi: Make semihosting code hand out its own file descriptors Currently the Arm semihosting code returns the guest file descriptors (handles) which are simply the fd values from the host OS or the remote gdbstub. Part of the semihosting 2.0 specification requires that we implement special handling of opening a ":semihosting-features" filename. Guest fds which result from opening the special file won't correspond to host fds, so to ensure that we don't end up with duplicate fds we need to have QEMU code control the allocation of the fd values we give the guest. Add in an abstraction layer which lets us allocate new guest FD values, and translate from a guest FD value back to the host one. This also fixes an odd hole where a semihosting guest could use the semihosting API to read, write or close file descriptors that it had never allocated but which were being used by QEMU itself. (This isn't a security hole, because enabling semihosting permits the guest to do arbitrary file access to the whole host filesystem, and so should only be done if the guest is completely trusted.) Currently the only kind of guest fd is one which maps to a host fd, but in a following commit we will add one which maps to the :semihosting-features magic data. If the guest is migrated with an open semihosting file descriptor then subsequent attempts to use the fd will all fail; this is not a change from the previous situation (where the host fd being used on the source end would not be re-opened on the destination end). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20190916141544.17540-5-peter.maydell@linaro.org
2019-09-16 10:15:33 -04:00
case TARGET_SYS_READC:
semihost_sys_read_gf(cs, common_semi_readc_cb, &console_in_gf,
common_semi_stack_bottom(cs) - 1, 1);
break;
case TARGET_SYS_ISERROR:
GET_ARG(0);
common_semi_set_ret(cs, (target_long)arg0 < 0);
break;
case TARGET_SYS_ISTTY:
GET_ARG(0);
semihost_sys_isatty(cs, common_semi_istty_cb, arg0);
break;
target/arm/arm-semi: Make semihosting code hand out its own file descriptors Currently the Arm semihosting code returns the guest file descriptors (handles) which are simply the fd values from the host OS or the remote gdbstub. Part of the semihosting 2.0 specification requires that we implement special handling of opening a ":semihosting-features" filename. Guest fds which result from opening the special file won't correspond to host fds, so to ensure that we don't end up with duplicate fds we need to have QEMU code control the allocation of the fd values we give the guest. Add in an abstraction layer which lets us allocate new guest FD values, and translate from a guest FD value back to the host one. This also fixes an odd hole where a semihosting guest could use the semihosting API to read, write or close file descriptors that it had never allocated but which were being used by QEMU itself. (This isn't a security hole, because enabling semihosting permits the guest to do arbitrary file access to the whole host filesystem, and so should only be done if the guest is completely trusted.) Currently the only kind of guest fd is one which maps to a host fd, but in a following commit we will add one which maps to the :semihosting-features magic data. If the guest is migrated with an open semihosting file descriptor then subsequent attempts to use the fd will all fail; this is not a change from the previous situation (where the host fd being used on the source end would not be re-opened on the destination end). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20190916141544.17540-5-peter.maydell@linaro.org
2019-09-16 10:15:33 -04:00
case TARGET_SYS_SEEK:
GET_ARG(0);
GET_ARG(1);
semihost_sys_lseek(cs, common_semi_seek_cb, arg0, arg1, GDB_SEEK_SET);
break;
target/arm/arm-semi: Make semihosting code hand out its own file descriptors Currently the Arm semihosting code returns the guest file descriptors (handles) which are simply the fd values from the host OS or the remote gdbstub. Part of the semihosting 2.0 specification requires that we implement special handling of opening a ":semihosting-features" filename. Guest fds which result from opening the special file won't correspond to host fds, so to ensure that we don't end up with duplicate fds we need to have QEMU code control the allocation of the fd values we give the guest. Add in an abstraction layer which lets us allocate new guest FD values, and translate from a guest FD value back to the host one. This also fixes an odd hole where a semihosting guest could use the semihosting API to read, write or close file descriptors that it had never allocated but which were being used by QEMU itself. (This isn't a security hole, because enabling semihosting permits the guest to do arbitrary file access to the whole host filesystem, and so should only be done if the guest is completely trusted.) Currently the only kind of guest fd is one which maps to a host fd, but in a following commit we will add one which maps to the :semihosting-features magic data. If the guest is migrated with an open semihosting file descriptor then subsequent attempts to use the fd will all fail; this is not a change from the previous situation (where the host fd being used on the source end would not be re-opened on the destination end). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20190916141544.17540-5-peter.maydell@linaro.org
2019-09-16 10:15:33 -04:00
case TARGET_SYS_FLEN:
GET_ARG(0);
semihost_sys_flen(cs, common_semi_flen_fstat_cb, common_semi_cb,
arg0, common_semi_flen_buf(cs));
break;
target/arm/arm-semi: Make semihosting code hand out its own file descriptors Currently the Arm semihosting code returns the guest file descriptors (handles) which are simply the fd values from the host OS or the remote gdbstub. Part of the semihosting 2.0 specification requires that we implement special handling of opening a ":semihosting-features" filename. Guest fds which result from opening the special file won't correspond to host fds, so to ensure that we don't end up with duplicate fds we need to have QEMU code control the allocation of the fd values we give the guest. Add in an abstraction layer which lets us allocate new guest FD values, and translate from a guest FD value back to the host one. This also fixes an odd hole where a semihosting guest could use the semihosting API to read, write or close file descriptors that it had never allocated but which were being used by QEMU itself. (This isn't a security hole, because enabling semihosting permits the guest to do arbitrary file access to the whole host filesystem, and so should only be done if the guest is completely trusted.) Currently the only kind of guest fd is one which maps to a host fd, but in a following commit we will add one which maps to the :semihosting-features magic data. If the guest is migrated with an open semihosting file descriptor then subsequent attempts to use the fd will all fail; this is not a change from the previous situation (where the host fd being used on the source end would not be re-opened on the destination end). Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-id: 20190916141544.17540-5-peter.maydell@linaro.org
2019-09-16 10:15:33 -04:00
case TARGET_SYS_TMPNAM:
{
int len;
char *p;
GET_ARG(0);
GET_ARG(1);
GET_ARG(2);
len = asprintf(&s, "%s/qemu-%x%02x", g_get_tmp_dir(),
getpid(), (int)arg1 & 0xff);
if (len < 0) {
common_semi_set_ret(cs, -1);
break;
}
/* Allow for trailing NUL */
len++;
/* Make sure there's enough space in the buffer */
if (len > arg2) {
free(s);
common_semi_set_ret(cs, -1);
break;
}
p = lock_user(VERIFY_WRITE, arg0, len, 0);
if (!p) {
free(s);
goto do_fault;
}
memcpy(p, s, len);
unlock_user(p, arg0, len);
free(s);
common_semi_set_ret(cs, 0);
break;
}
case TARGET_SYS_REMOVE:
GET_ARG(0);
GET_ARG(1);
semihost_sys_remove(cs, common_semi_cb, arg0, arg1 + 1);
break;
case TARGET_SYS_RENAME:
GET_ARG(0);
GET_ARG(1);
GET_ARG(2);
GET_ARG(3);
semihost_sys_rename(cs, common_semi_cb, arg0, arg1 + 1, arg2, arg3 + 1);
break;
case TARGET_SYS_CLOCK:
common_semi_set_ret(cs, clock() / (CLOCKS_PER_SEC / 100));
break;
case TARGET_SYS_TIME:
ul_ret = time(NULL);
common_semi_cb(cs, ul_ret, ul_ret == -1 ? errno : 0);
break;
case TARGET_SYS_SYSTEM:
GET_ARG(0);
GET_ARG(1);
semihost_sys_system(cs, common_semi_cb, arg0, arg1 + 1);
break;
case TARGET_SYS_ERRNO:
common_semi_set_ret(cs, get_swi_errno(cs));
break;
case TARGET_SYS_GET_CMDLINE:
{
/* Build a command-line from the original argv.
*
* The inputs are:
* * arg0, pointer to a buffer of at least the size
* specified in arg1.
* * arg1, size of the buffer pointed to by arg0 in
* bytes.
*
* The outputs are:
* * arg0, pointer to null-terminated string of the
* command line.
* * arg1, length of the string pointed to by arg0.
*/
char *output_buffer;
size_t input_size;
size_t output_size;
int status = 0;
#if !defined(CONFIG_USER_ONLY)
const char *cmdline;
#else
TaskState *ts = cs->opaque;
#endif
GET_ARG(0);
GET_ARG(1);
input_size = arg1;
/* Compute the size of the output string. */
#if !defined(CONFIG_USER_ONLY)
cmdline = semihosting_get_cmdline();
if (cmdline == NULL) {
cmdline = ""; /* Default to an empty line. */
}
output_size = strlen(cmdline) + 1; /* Count terminating 0. */
#else
unsigned int i;
output_size = ts->info->env_strings - ts->info->arg_strings;
if (!output_size) {
/*
* We special-case the "empty command line" case (argc==0).
* Just provide the terminating 0.
*/
output_size = 1;
}
#endif
if (output_size > input_size) {
/* Not enough space to store command-line arguments. */
common_semi_cb(cs, -1, E2BIG);
break;
}
/* Adjust the command-line length. */
if (SET_ARG(1, output_size - 1)) {
/* Couldn't write back to argument block */
goto do_fault;
}
/* Lock the buffer on the ARM side. */
output_buffer = lock_user(VERIFY_WRITE, arg0, output_size, 0);
if (!output_buffer) {
goto do_fault;
}
/* Copy the command-line arguments. */
#if !defined(CONFIG_USER_ONLY)
pstrcpy(output_buffer, output_size, cmdline);
#else
if (output_size == 1) {
/* Empty command-line. */
output_buffer[0] = '\0';
goto out;
}
if (copy_from_user(output_buffer, ts->info->arg_strings,
output_size)) {
unlock_user(output_buffer, arg0, 0);
goto do_fault;
}
/* Separate arguments by white spaces. */
for (i = 0; i < output_size - 1; i++) {
if (output_buffer[i] == 0) {
output_buffer[i] = ' ';
}
}
out:
#endif
/* Unlock the buffer on the ARM side. */
unlock_user(output_buffer, arg0, output_size);
common_semi_cb(cs, status, 0);
}
break;
case TARGET_SYS_HEAPINFO:
{
target_ulong retvals[4];
int i;
#ifdef CONFIG_USER_ONLY
TaskState *ts = cs->opaque;
target_ulong limit;
#else
LayoutInfo info = common_semi_find_bases(cs);
#endif
GET_ARG(0);
#ifdef CONFIG_USER_ONLY
/*
* Some C libraries assume the heap immediately follows .bss, so
* allocate it using sbrk.
*/
if (!ts->heap_limit) {
abi_ulong ret;
ts->heap_base = do_brk(0);
semihosting: Change internal common-semi interfaces to use CPUState * This makes all of the internal interfaces architecture-independent and renames the internal functions to use the 'common_semi' prefix instead of 'arm' or 'arm_semi'. To do this, some new architecture-specific internal helper functions were created: static inline target_ulong common_semi_arg(CPUState *cs, int argno) Returns the argno'th semihosting argument, where argno can be either 0 or 1. static inline void common_semi_set_ret(CPUState *cs, target_ulong ret) Sets the semihosting return value. static inline bool common_semi_sys_exit_extended(CPUState *cs, int nr) This detects whether the specified semihosting call, which is either TARGET_SYS_EXIT or TARGET_SYS_EXIT_EXTENDED should be executed using the TARGET_SYS_EXIT_EXTENDED semantics. static inline target_ulong common_semi_rambase(CPUState *cs) Returns the base of RAM region used for heap and stack. This is used to construct plausible values for the SYS_HEAPINFO call. In addition, several existing functions have been changed to flag areas of code which are architecture specific: static target_ulong common_semi_flen_buf(CPUState *cs) Returns the current stack pointer minus 64, which is where a stat structure will be placed on the stack #define GET_ARG(n) This fetches arguments from the semihosting command's argument block. The address of this is available implicitly through the local 'args' variable. This is *mostly* architecture independent, but does depend on the current ABI's notion of the size of a 'long' parameter, which may need run-time checks (as it does on AARCH64) #define SET_ARG(n, val) This mirrors GET_ARG and stores data back into the argument block. Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20210107170717.2098982-4-keithp@keithp.com> Message-Id: <20210108224256.2321-15-alex.bennee@linaro.org>
2021-01-08 17:42:50 -05:00
limit = ts->heap_base + COMMON_SEMI_HEAP_SIZE;
/* Try a big heap, and reduce the size if that fails. */
for (;;) {
ret = do_brk(limit);
if (ret >= limit) {
break;
}
limit = (ts->heap_base >> 1) + (limit >> 1);
}
ts->heap_limit = limit;
}
retvals[0] = ts->heap_base;
retvals[1] = ts->heap_limit;
retvals[2] = ts->stack_base;
retvals[3] = 0; /* Stack limit. */
#else
retvals[0] = info.heapbase; /* Heap Base */
retvals[1] = info.heaplimit; /* Heap Limit */
retvals[2] = info.heaplimit; /* Stack base */
retvals[3] = info.heapbase; /* Stack limit. */
#endif
for (i = 0; i < ARRAY_SIZE(retvals); i++) {
bool fail;
if (is_64bit_semihosting(env)) {
fail = put_user_u64(retvals[i], arg0 + i * 8);
} else {
fail = put_user_u32(retvals[i], arg0 + i * 4);
}
if (fail) {
/* Couldn't write back to argument block */
goto do_fault;
}
}
common_semi_set_ret(cs, 0);
}
break;
case TARGET_SYS_EXIT:
case TARGET_SYS_EXIT_EXTENDED:
semihosting: Change internal common-semi interfaces to use CPUState * This makes all of the internal interfaces architecture-independent and renames the internal functions to use the 'common_semi' prefix instead of 'arm' or 'arm_semi'. To do this, some new architecture-specific internal helper functions were created: static inline target_ulong common_semi_arg(CPUState *cs, int argno) Returns the argno'th semihosting argument, where argno can be either 0 or 1. static inline void common_semi_set_ret(CPUState *cs, target_ulong ret) Sets the semihosting return value. static inline bool common_semi_sys_exit_extended(CPUState *cs, int nr) This detects whether the specified semihosting call, which is either TARGET_SYS_EXIT or TARGET_SYS_EXIT_EXTENDED should be executed using the TARGET_SYS_EXIT_EXTENDED semantics. static inline target_ulong common_semi_rambase(CPUState *cs) Returns the base of RAM region used for heap and stack. This is used to construct plausible values for the SYS_HEAPINFO call. In addition, several existing functions have been changed to flag areas of code which are architecture specific: static target_ulong common_semi_flen_buf(CPUState *cs) Returns the current stack pointer minus 64, which is where a stat structure will be placed on the stack #define GET_ARG(n) This fetches arguments from the semihosting command's argument block. The address of this is available implicitly through the local 'args' variable. This is *mostly* architecture independent, but does depend on the current ABI's notion of the size of a 'long' parameter, which may need run-time checks (as it does on AARCH64) #define SET_ARG(n, val) This mirrors GET_ARG and stores data back into the argument block. Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Alistair Francis <alistair.francis@wdc.com> Message-Id: <20210107170717.2098982-4-keithp@keithp.com> Message-Id: <20210108224256.2321-15-alex.bennee@linaro.org>
2021-01-08 17:42:50 -05:00
if (common_semi_sys_exit_extended(cs, nr)) {
/*
* The A64 version of SYS_EXIT takes a parameter block,
* so the application-exit type can return a subcode which
* is the exit status code from the application.
* SYS_EXIT_EXTENDED is an a new-in-v2.0 optional function
* which allows A32/T32 guests to also provide a status code.
*/
GET_ARG(0);
GET_ARG(1);
if (arg0 == ADP_Stopped_ApplicationExit) {
ret = arg1;
} else {
ret = 1;
}
} else {
/*
* The A32/T32 version of SYS_EXIT specifies only
* Stopped_ApplicationExit as normal exit, but does not
* allow the guest to specify the exit status code.
* Everything else is considered an error.
*/
ret = (args == ADP_Stopped_ApplicationExit) ? 0 : 1;
}
gdb_exit(ret);
exit(ret);
case TARGET_SYS_ELAPSED:
elapsed = get_clock() - clock_start;
if (sizeof(target_ulong) == 8) {
if (SET_ARG(0, elapsed)) {
goto do_fault;
}
} else {
if (SET_ARG(0, (uint32_t) elapsed) ||
SET_ARG(1, (uint32_t) (elapsed >> 32))) {
goto do_fault;
}
}
common_semi_set_ret(cs, 0);
break;
case TARGET_SYS_TICKFREQ:
/* qemu always uses nsec */
common_semi_set_ret(cs, 1000000000);
break;
case TARGET_SYS_SYNCCACHE:
/*
* Clean the D-cache and invalidate the I-cache for the specified
* virtual address range. This is a nop for us since we don't
* implement caches. This is only present on A64.
*/
if (common_semi_has_synccache(env)) {
common_semi_set_ret(cs, 0);
break;
}
/* fall through */
default:
fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);
cpu_dump_state(cs, stderr, 0);
abort();
do_fault:
common_semi_cb(cs, -1, EFAULT);
break;
}
}