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diff --git a/semihosting/arm-compat-semi.c b/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://static.docs.arm.com/100863/0200/semihosting.pdf
+ *
+ * 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 "cpu.h"
+#include "semihosting/semihost.h"
+#include "semihosting/console.h"
+#include "semihosting/common-semi.h"
+#include "qemu/log.h"
+#include "qemu/timer.h"
+#ifdef CONFIG_USER_ONLY
+#include "qemu.h"
+
+#define COMMON_SEMI_HEAP_SIZE (128 * 1024 * 1024)
+#else
+#include "exec/gdbstub.h"
+#include "qemu/cutils.h"
+#ifdef TARGET_ARM
+#include "hw/arm/boot.h"
+#endif
+#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
+
+#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,
+ O_RDWR | O_BINARY,
+ O_WRONLY | O_CREAT | O_TRUNC,
+ O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
+ O_RDWR | O_CREAT | O_TRUNC,
+ O_RDWR | O_CREAT | O_TRUNC | O_BINARY,
+ O_WRONLY | O_CREAT | O_APPEND,
+ O_WRONLY | O_CREAT | O_APPEND | O_BINARY,
+ O_RDWR | O_CREAT | O_APPEND,
+ O_RDWR | O_CREAT | O_APPEND | O_BINARY
+};
+
+typedef enum GuestFDType {
+ GuestFDUnused = 0,
+ GuestFDHost = 1,
+ GuestFDGDB = 2,
+ GuestFDFeatureFile = 3,
+} GuestFDType;
+
+/*
+ * Guest file descriptors are integer indexes into an array of
+ * these structures (we will dynamically resize as necessary).
+ */
+typedef struct GuestFD {
+ GuestFDType type;
+ union {
+ int hostfd;
+ target_ulong featurefile_offset;
+ };
+} GuestFD;
+
+static GArray *guestfd_array;
+
+#ifndef CONFIG_USER_ONLY
+#include "exec/address-spaces.h"
+/*
+ * Find the base of a RAM region containing the specified address
+ */
+static inline hwaddr
+common_semi_find_region_base(hwaddr addr)
+{
+ MemoryRegion *subregion;
+
+ /*
+ * Find the chunk of R/W memory containing the address. This is
+ * used for the SYS_HEAPINFO semihosting call, which should
+ * probably be using information from the loaded application.
+ */
+ QTAILQ_FOREACH(subregion, &get_system_memory()->subregions,
+ subregions_link) {
+ if (subregion->ram && !subregion->readonly) {
+ Int128 top128 = int128_add(int128_make64(subregion->addr),
+ subregion->size);
+ Int128 addr128 = int128_make64(addr);
+ if (subregion->addr <= addr && int128_lt(addr128, top128)) {
+ return subregion->addr;
+ }
+ }
+ }
+ return 0;
+}
+#endif
+
+#ifdef TARGET_ARM
+static inline target_ulong
+common_semi_arg(CPUState *cs, int argno)
+{
+ ARMCPU *cpu = ARM_CPU(cs);
+ CPUARMState *env = &cpu->env;
+ if (is_a64(env)) {
+ return env->xregs[argno];
+ } else {
+ return env->regs[argno];
+ }
+}
+
+static inline void
+common_semi_set_ret(CPUState *cs, target_ulong ret)
+{
+ ARMCPU *cpu = ARM_CPU(cs);
+ CPUARMState *env = &cpu->env;
+ if (is_a64(env)) {
+ env->xregs[0] = ret;
+ } else {
+ env->regs[0] = ret;
+ }
+}
+
+static inline bool
+common_semi_sys_exit_extended(CPUState *cs, int nr)
+{
+ return (nr == TARGET_SYS_EXIT_EXTENDED || is_a64(cs->env_ptr));
+}
+
+#ifndef CONFIG_USER_ONLY
+#include "hw/arm/boot.h"
+static inline target_ulong
+common_semi_rambase(CPUState *cs)
+{
+ CPUArchState *env = cs->env_ptr;
+ const struct arm_boot_info *info = env->boot_info;
+ target_ulong sp;
+
+ if (info) {
+ return info->loader_start;
+ }
+
+ if (is_a64(env)) {
+ sp = env->xregs[31];
+ } else {
+ sp = env->regs[13];
+ }
+ return common_semi_find_region_base(sp);
+}
+#endif
+
+#endif /* TARGET_ARM */
+
+#ifdef TARGET_RISCV
+static inline target_ulong
+common_semi_arg(CPUState *cs, int argno)
+{
+ RISCVCPU *cpu = RISCV_CPU(cs);
+ CPURISCVState *env = &cpu->env;
+ return env->gpr[xA0 + argno];
+}
+
+static inline void
+common_semi_set_ret(CPUState *cs, target_ulong ret)
+{
+ RISCVCPU *cpu = RISCV_CPU(cs);
+ CPURISCVState *env = &cpu->env;
+ env->gpr[xA0] = ret;
+}
+
+static inline bool
+common_semi_sys_exit_extended(CPUState *cs, int nr)
+{
+ return (nr == TARGET_SYS_EXIT_EXTENDED || sizeof(target_ulong) == 8);
+}
+
+#ifndef CONFIG_USER_ONLY
+
+static inline target_ulong
+common_semi_rambase(CPUState *cs)
+{
+ RISCVCPU *cpu = RISCV_CPU(cs);
+ CPURISCVState *env = &cpu->env;
+ return common_semi_find_region_base(env->gpr[xSP]);
+}
+#endif
+
+#endif
+
+/*
+ * Allocate a new guest file descriptor and return it; if we
+ * couldn't allocate a new fd then return -1.
+ * This is a fairly simplistic implementation because we don't
+ * expect that most semihosting guest programs will make very
+ * heavy use of opening and closing fds.
+ */
+static int alloc_guestfd(void)
+{
+ guint i;
+
+ if (!guestfd_array) {
+ /* New entries zero-initialized, i.e. type GuestFDUnused */
+ guestfd_array = g_array_new(FALSE, TRUE, sizeof(GuestFD));
+ }
+
+ /* SYS_OPEN should return nonzero handle on success. Start guestfd from 1 */
+ for (i = 1; i < guestfd_array->len; i++) {
+ GuestFD *gf = &g_array_index(guestfd_array, GuestFD, i);
+
+ if (gf->type == GuestFDUnused) {
+ return i;
+ }
+ }
+
+ /* All elements already in use: expand the array */
+ g_array_set_size(guestfd_array, i + 1);
+ return i;
+}
+
+/*
+ * Look up the guestfd in the data structure; return NULL
+ * for out of bounds, but don't check whether the slot is unused.
+ * This is used internally by the other guestfd functions.
+ */
+static GuestFD *do_get_guestfd(int guestfd)
+{
+ if (!guestfd_array) {
+ return NULL;
+ }
+
+ if (guestfd <= 0 || guestfd >= guestfd_array->len) {
+ return NULL;
+ }
+
+ return &g_array_index(guestfd_array, GuestFD, guestfd);
+}
+
+/*
+ * Associate the specified guest fd (which must have been
+ * allocated via alloc_fd() and not previously used) with
+ * the specified host/gdb fd.
+ */
+static void associate_guestfd(int guestfd, int hostfd)
+{
+ GuestFD *gf = do_get_guestfd(guestfd);
+
+ assert(gf);
+ gf->type = use_gdb_syscalls() ? GuestFDGDB : GuestFDHost;
+ gf->hostfd = hostfd;
+}
+
+/*
+ * Deallocate the specified guest file descriptor. This doesn't
+ * close the host fd, it merely undoes the work of alloc_fd().
+ */
+static void dealloc_guestfd(int guestfd)
+{
+ GuestFD *gf = do_get_guestfd(guestfd);
+
+ assert(gf);
+ gf->type = GuestFDUnused;
+}
+
+/*
+ * Given a guest file descriptor, get the associated struct.
+ * If the fd is not valid, return NULL. This is the function
+ * used by the various semihosting calls to validate a handle
+ * from the guest.
+ * Note: calling alloc_guestfd() or dealloc_guestfd() will
+ * invalidate any GuestFD* obtained by calling this function.
+ */
+static GuestFD *get_guestfd(int guestfd)
+{
+ GuestFD *gf = do_get_guestfd(guestfd);
+
+ if (!gf || gf->type == GuestFDUnused) {
+ return NULL;
+ }
+ return gf;
+}
+
+/*
+ * 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 "exec/softmmu-semi.h"
+#endif
+
+static inline uint32_t set_swi_errno(CPUState *cs, uint32_t code)
+{
+ if (code == (uint32_t)-1) {
+#ifdef CONFIG_USER_ONLY
+ TaskState *ts = cs->opaque;
+
+ ts->swi_errno = errno;
+#else
+ syscall_err = errno;
+#endif
+ }
+ return code;
+}
+
+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 target_ulong common_semi_syscall_len;
+
+static void common_semi_cb(CPUState *cs, target_ulong ret, target_ulong err)
+{
+ target_ulong reg0 = common_semi_arg(cs, 0);
+
+ if (ret == (target_ulong)-1) {
+ errno = err;
+ set_swi_errno(cs, -1);
+ reg0 = ret;
+ } else {
+ /* Fixup syscalls that use nonstardard return conventions. */
+ switch (reg0) {
+ case TARGET_SYS_WRITE:
+ case TARGET_SYS_READ:
+ reg0 = common_semi_syscall_len - ret;
+ break;
+ case TARGET_SYS_SEEK:
+ reg0 = 0;
+ break;
+ default:
+ reg0 = ret;
+ break;
+ }
+ }
+ common_semi_set_ret(cs, reg0);
+}
+
+static target_ulong common_semi_flen_buf(CPUState *cs)
+{
+ target_ulong sp;
+#ifdef TARGET_ARM
+ /* 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.
+ */
+ ARMCPU *cpu = ARM_CPU(cs);
+ CPUARMState *env = &cpu->env;
+
+ if (is_a64(env)) {
+ sp = env->xregs[31];
+ } else {
+ sp = env->regs[13];
+ }
+#endif
+#ifdef TARGET_RISCV
+ RISCVCPU *cpu = RISCV_CPU(cs);
+ CPURISCVState *env = &cpu->env;
+
+ sp = env->gpr[xSP];
+#endif
+
+ return sp - 64;
+}
+
+static void
+common_semi_flen_cb(CPUState *cs, target_ulong ret, target_ulong err)
+{
+ /* The size is always stored in big-endian order, extract
+ the value. We assume the size always fit in 32 bits. */
+ uint32_t size;
+ cpu_memory_rw_debug(cs, common_semi_flen_buf(cs) + 32,
+ (uint8_t *)&size, 4, 0);
+ size = be32_to_cpu(size);
+ common_semi_set_ret(cs, size);
+ errno = err;
+ set_swi_errno(cs, -1);
+}
+
+static int common_semi_open_guestfd;
+
+static void
+common_semi_open_cb(CPUState *cs, target_ulong ret, target_ulong err)
+{
+ if (ret == (target_ulong)-1) {
+ errno = err;
+ set_swi_errno(cs, -1);
+ dealloc_guestfd(common_semi_open_guestfd);
+ } else {
+ associate_guestfd(common_semi_open_guestfd, ret);
+ ret = common_semi_open_guestfd;
+ }
+ common_semi_set_ret(cs, ret);
+}
+
+static target_ulong
+common_semi_gdb_syscall(CPUState *cs, gdb_syscall_complete_cb cb,
+ const char *fmt, ...)
+{
+ va_list va;
+
+ va_start(va, fmt);
+ gdb_do_syscallv(cb, fmt, va);
+ va_end(va);
+
+ /*
+ * FIXME: in softmmu mode, the gdbstub will schedule our callback
+ * to occur, but will not actually call it to complete the syscall
+ * until after this function has returned and we are back in the
+ * CPU main loop. Therefore callers to this function must not
+ * do anything with its return value, because it is not necessarily
+ * the result of the syscall, but could just be the old value of X0.
+ * The only thing safe to do with this is that the callers of
+ * do_common_semihosting() will write it straight back into X0.
+ * (In linux-user mode, the callback will have happened before
+ * gdb_do_syscallv() returns.)
+ *
+ * We should tidy this up so neither this function nor
+ * do_common_semihosting() return a value, so the mistake of
+ * doing something with the return value is not possible to make.
+ */
+
+ return common_semi_arg(cs, 0);
+}
+
+/*
+ * Types for functions implementing various semihosting calls
+ * for specific types of guest file descriptor. These must all
+ * do the work and return the required return value for the guest,
+ * setting the guest errno if appropriate.
+ */
+typedef uint32_t sys_closefn(CPUState *cs, GuestFD *gf);
+typedef uint32_t sys_writefn(CPUState *cs, GuestFD *gf,
+ target_ulong buf, uint32_t len);
+typedef uint32_t sys_readfn(CPUState *cs, GuestFD *gf,
+ target_ulong buf, uint32_t len);
+typedef uint32_t sys_isattyfn(CPUState *cs, GuestFD *gf);
+typedef uint32_t sys_seekfn(CPUState *cs, GuestFD *gf,
+ target_ulong offset);
+typedef uint32_t sys_flenfn(CPUState *cs, GuestFD *gf);
+
+static uint32_t host_closefn(CPUState *cs, GuestFD *gf)
+{
+ /*
+ * Only close the underlying host fd if it's one we opened on behalf
+ * of the guest in SYS_OPEN.
+ */
+ if (gf->hostfd == STDIN_FILENO ||
+ gf->hostfd == STDOUT_FILENO ||
+ gf->hostfd == STDERR_FILENO) {
+ return 0;
+ }
+ return set_swi_errno(cs, close(gf->hostfd));
+}
+
+static uint32_t host_writefn(CPUState *cs, GuestFD *gf,
+ target_ulong buf, uint32_t len)
+{
+ CPUArchState *env = cs->env_ptr;
+ uint32_t ret;
+ char *s = lock_user(VERIFY_READ, buf, len, 1);
+ (void) env; /* Used in arm softmmu lock_user implicitly */
+ if (!s) {
+ /* Return bytes not written on error */
+ return len;
+ }
+ ret = set_swi_errno(cs, write(gf->hostfd, s, len));
+ unlock_user(s, buf, 0);
+ if (ret == (uint32_t)-1) {
+ ret = 0;
+ }
+ /* Return bytes not written */
+ return len - ret;
+}
+
+static uint32_t host_readfn(CPUState *cs, GuestFD *gf,
+ target_ulong buf, uint32_t len)
+{
+ CPUArchState *env = cs->env_ptr;
+ uint32_t ret;
+ char *s = lock_user(VERIFY_WRITE, buf, len, 0);
+ (void) env; /* Used in arm softmmu lock_user implicitly */
+ if (!s) {
+ /* return bytes not read */
+ return len;
+ }
+ do {
+ ret = set_swi_errno(cs, read(gf->hostfd, s, len));
+ } while (ret == -1 && errno == EINTR);
+ unlock_user(s, buf, len);
+ if (ret == (uint32_t)-1) {
+ ret = 0;
+ }
+ /* Return bytes not read */
+ return len - ret;
+}
+
+static uint32_t host_isattyfn(CPUState *cs, GuestFD *gf)
+{
+ return isatty(gf->hostfd);
+}
+
+static uint32_t host_seekfn(CPUState *cs, GuestFD *gf, target_ulong offset)
+{
+ uint32_t ret = set_swi_errno(cs, lseek(gf->hostfd, offset, SEEK_SET));
+ if (ret == (uint32_t)-1) {
+ return -1;
+ }
+ return 0;
+}
+
+static uint32_t host_flenfn(CPUState *cs, GuestFD *gf)
+{
+ struct stat buf;
+ uint32_t ret = set_swi_errno(cs, fstat(gf->hostfd, &buf));
+ if (ret == (uint32_t)-1) {
+ return -1;
+ }
+ return buf.st_size;
+}
+
+static uint32_t gdb_closefn(CPUState *cs, GuestFD *gf)
+{
+ return common_semi_gdb_syscall(cs, common_semi_cb, "close,%x", gf->hostfd);
+}
+
+static uint32_t gdb_writefn(CPUState *cs, GuestFD *gf,
+ target_ulong buf, uint32_t len)
+{
+ common_semi_syscall_len = len;
+ return common_semi_gdb_syscall(cs, common_semi_cb, "write,%x,%x,%x",
+ gf->hostfd, buf, len);
+}
+
+static uint32_t gdb_readfn(CPUState *cs, GuestFD *gf,
+ target_ulong buf, uint32_t len)
+{
+ common_semi_syscall_len = len;
+ return common_semi_gdb_syscall(cs, common_semi_cb, "read,%x,%x,%x",
+ gf->hostfd, buf, len);
+}
+
+static uint32_t gdb_isattyfn(CPUState *cs, GuestFD *gf)
+{
+ return common_semi_gdb_syscall(cs, common_semi_cb, "isatty,%x", gf->hostfd);
+}
+
+static uint32_t gdb_seekfn(CPUState *cs, GuestFD *gf, target_ulong offset)
+{
+ return common_semi_gdb_syscall(cs, common_semi_cb, "lseek,%x,%x,0",
+ gf->hostfd, offset);
+}
+
+static uint32_t gdb_flenfn(CPUState *cs, GuestFD *gf)
+{
+ return common_semi_gdb_syscall(cs, common_semi_flen_cb, "fstat,%x,%x",
+ gf->hostfd, common_semi_flen_buf(cs));
+}
+
+#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 */
+};
+
+static void init_featurefile_guestfd(int guestfd)
+{
+ GuestFD *gf = do_get_guestfd(guestfd);
+
+ assert(gf);
+ gf->type = GuestFDFeatureFile;
+ gf->featurefile_offset = 0;
+}
+
+static uint32_t featurefile_closefn(CPUState *cs, GuestFD *gf)
+{
+ /* Nothing to do */
+ return 0;
+}
+
+static uint32_t featurefile_writefn(CPUState *cs, GuestFD *gf,
+ target_ulong buf, uint32_t len)
+{
+ /* This fd can never be open for writing */
+
+ errno = EBADF;
+ return set_swi_errno(cs, -1);
+}
+
+static uint32_t featurefile_readfn(CPUState *cs, GuestFD *gf,
+ target_ulong buf, uint32_t len)
+{
+ CPUArchState *env = cs->env_ptr;
+ uint32_t i;
+ char *s;
+
+ (void) env; /* Used in arm softmmu lock_user implicitly */
+ s = lock_user(VERIFY_WRITE, buf, len, 0);
+ if (!s) {
+ return len;
+ }
+
+ for (i = 0; i < len; i++) {
+ if (gf->featurefile_offset >= sizeof(featurefile_data)) {
+ break;
+ }
+ s[i] = featurefile_data[gf->featurefile_offset];
+ gf->featurefile_offset++;
+ }
+
+ unlock_user(s, buf, len);
+
+ /* Return number of bytes not read */
+ return len - i;
+}
+
+static uint32_t featurefile_isattyfn(CPUState *cs, GuestFD *gf)
+{
+ return 0;
+}
+
+static uint32_t featurefile_seekfn(CPUState *cs, GuestFD *gf,
+ target_ulong offset)
+{
+ gf->featurefile_offset = offset;
+ return 0;
+}
+
+static uint32_t featurefile_flenfn(CPUState *cs, GuestFD *gf)
+{
+ return sizeof(featurefile_data);
+}
+
+typedef struct GuestFDFunctions {
+ sys_closefn *closefn;
+ sys_writefn *writefn;
+ sys_readfn *readfn;
+ sys_isattyfn *isattyfn;
+ sys_seekfn *seekfn;
+ sys_flenfn *flenfn;
+} GuestFDFunctions;
+
+static const GuestFDFunctions guestfd_fns[] = {
+ [GuestFDHost] = {
+ .closefn = host_closefn,
+ .writefn = host_writefn,
+ .readfn = host_readfn,
+ .isattyfn = host_isattyfn,
+ .seekfn = host_seekfn,
+ .flenfn = host_flenfn,
+ },
+ [GuestFDGDB] = {
+ .closefn = gdb_closefn,
+ .writefn = gdb_writefn,
+ .readfn = gdb_readfn,
+ .isattyfn = gdb_isattyfn,
+ .seekfn = gdb_seekfn,
+ .flenfn = gdb_flenfn,
+ },
+ [GuestFDFeatureFile] = {
+ .closefn = featurefile_closefn,
+ .writefn = featurefile_writefn,
+ .readfn = featurefile_readfn,
+ .isattyfn = featurefile_isattyfn,
+ .seekfn = featurefile_seekfn,
+ .flenfn = featurefile_flenfn,
+ },
+};
+
+/* Read the input value from the argument block; fail the semihosting
+ * call if the memory read fails.
+ */
+#ifdef TARGET_ARM
+#define GET_ARG(n) do { \
+ if (is_a64(env)) { \
+ if (get_user_u64(arg ## n, args + (n) * 8)) { \
+ errno = EFAULT; \
+ return set_swi_errno(cs, -1); \
+ } \
+ } else { \
+ if (get_user_u32(arg ## n, args + (n) * 4)) { \
+ errno = EFAULT; \
+ return set_swi_errno(cs, -1); \
+ } \
+ } \
+} while (0)
+
+#define SET_ARG(n, val) \
+ (is_a64(env) ? \
+ put_user_u64(val, args + (n) * 8) : \
+ put_user_u32(val, args + (n) * 4))
+#endif
+
+#ifdef TARGET_RISCV
+
+/*
+ * get_user_ual is defined as get_user_u32 in softmmu-semi.h,
+ * we need a macro that fetches a target_ulong
+ */
+#define get_user_utl(arg, p) \
+ ((sizeof(target_ulong) == 8) ? \
+ get_user_u64(arg, p) : \
+ get_user_u32(arg, p))
+
+/*
+ * put_user_ual is defined as put_user_u32 in softmmu-semi.h,
+ * we need a macro that stores a target_ulong
+ */
+#define put_user_utl(arg, p) \
+ ((sizeof(target_ulong) == 8) ? \
+ put_user_u64(arg, p) : \
+ put_user_u32(arg, p))
+
+#define GET_ARG(n) do { \
+ if (get_user_utl(arg ## n, args + (n) * sizeof(target_ulong))) { \
+ errno = EFAULT; \
+ return set_swi_errno(cs, -1); \
+ } \
+ } while (0)
+
+#define SET_ARG(n, val) \
+ put_user_utl(val, args + (n) * sizeof(target_ulong))
+#endif
+
+/*
+ * 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. We use 0xdeadbeef as the return value
+ * when there isn't a defined return value for the call.
+ */
+target_ulong do_common_semihosting(CPUState *cs)
+{
+ 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;
+ uint32_t len;
+ GuestFD *gf;
+ int64_t elapsed;
+
+ (void) env; /* Used implicitly by arm lock_user macro */
+ nr = common_semi_arg(cs, 0) & 0xffffffffU;
+ args = common_semi_arg(cs, 1);
+
+ switch (nr) {
+ case TARGET_SYS_OPEN:
+ {
+ int guestfd;
+
+ GET_ARG(0);
+ GET_ARG(1);
+ GET_ARG(2);
+ s = lock_user_string(arg0);
+ if (!s) {
+ errno = EFAULT;
+ return set_swi_errno(cs, -1);
+ }
+ if (arg1 >= 12) {
+ unlock_user(s, arg0, 0);
+ errno = EINVAL;
+ return set_swi_errno(cs, -1);
+ }
+
+ guestfd = alloc_guestfd();
+ if (guestfd < 0) {
+ unlock_user(s, arg0, 0);
+ errno = EMFILE;
+ return set_swi_errno(cs, -1);
+ }
+
+ if (strcmp(s, ":tt") == 0) {
+ int result_fileno;
+
+ /*
+ * We implement SH_EXT_STDOUT_STDERR, so:
+ * open for read == stdin
+ * open for write == stdout
+ * open for append == stderr
+ */
+ if (arg1 < 4) {
+ result_fileno = STDIN_FILENO;
+ } else if (arg1 < 8) {
+ result_fileno = STDOUT_FILENO;
+ } else {
+ result_fileno = STDERR_FILENO;
+ }
+ associate_guestfd(guestfd, result_fileno);
+ unlock_user(s, arg0, 0);
+ return guestfd;
+ }
+ if (strcmp(s, ":semihosting-features") == 0) {
+ unlock_user(s, arg0, 0);
+ /* We must fail opens for modes other than 0 ('r') or 1 ('rb') */
+ if (arg1 != 0 && arg1 != 1) {
+ dealloc_guestfd(guestfd);
+ errno = EACCES;
+ return set_swi_errno(cs, -1);
+ }
+ init_featurefile_guestfd(guestfd);
+ return guestfd;
+ }
+
+ if (use_gdb_syscalls()) {
+ common_semi_open_guestfd = guestfd;
+ ret = common_semi_gdb_syscall(cs, common_semi_open_cb,
+ "open,%s,%x,1a4", arg0, (int)arg2 + 1,
+ gdb_open_modeflags[arg1]);
+ } else {
+ ret = set_swi_errno(cs, open(s, open_modeflags[arg1], 0644));
+ if (ret == (uint32_t)-1) {
+ dealloc_guestfd(guestfd);
+ } else {
+ associate_guestfd(guestfd, ret);
+ ret = guestfd;
+ }
+ }
+ unlock_user(s, arg0, 0);
+ return ret;
+ }
+ case TARGET_SYS_CLOSE:
+ GET_ARG(0);
+
+ gf = get_guestfd(arg0);
+ if (!gf) {
+ errno = EBADF;
+ return set_swi_errno(cs, -1);
+ }
+
+ ret = guestfd_fns[gf->type].closefn(cs, gf);
+ dealloc_guestfd(arg0);
+ return ret;
+ case TARGET_SYS_WRITEC:
+ qemu_semihosting_console_outc(cs->env_ptr, args);
+ return 0xdeadbeef;
+ case TARGET_SYS_WRITE0:
+ return qemu_semihosting_console_outs(cs->env_ptr, args);
+ case TARGET_SYS_WRITE:
+ GET_ARG(0);
+ GET_ARG(1);
+ GET_ARG(2);
+ len = arg2;
+
+ gf = get_guestfd(arg0);
+ if (!gf) {
+ errno = EBADF;
+ return set_swi_errno(cs, -1);
+ }
+
+ return guestfd_fns[gf->type].writefn(cs, gf, arg1, len);
+ case TARGET_SYS_READ:
+ GET_ARG(0);
+ GET_ARG(1);
+ GET_ARG(2);
+ len = arg2;
+
+ gf = get_guestfd(arg0);
+ if (!gf) {
+ errno = EBADF;
+ return set_swi_errno(cs, -1);
+ }
+
+ return guestfd_fns[gf->type].readfn(cs, gf, arg1, len);
+ case TARGET_SYS_READC:
+ return qemu_semihosting_console_inc(cs->env_ptr);
+ case TARGET_SYS_ISERROR:
+ GET_ARG(0);
+ return (target_long) arg0 < 0 ? 1 : 0;
+ case TARGET_SYS_ISTTY:
+ GET_ARG(0);
+
+ gf = get_guestfd(arg0);
+ if (!gf) {
+ errno = EBADF;
+ return set_swi_errno(cs, -1);
+ }
+
+ return guestfd_fns[gf->type].isattyfn(cs, gf);
+ case TARGET_SYS_SEEK:
+ GET_ARG(0);
+ GET_ARG(1);
+
+ gf = get_guestfd(arg0);
+ if (!gf) {
+ errno = EBADF;
+ return set_swi_errno(cs, -1);
+ }
+
+ return guestfd_fns[gf->type].seekfn(cs, gf, arg1);
+ case TARGET_SYS_FLEN:
+ GET_ARG(0);
+
+ gf = get_guestfd(arg0);
+ if (!gf) {
+ errno = EBADF;
+ return set_swi_errno(cs, -1);
+ }
+
+ return guestfd_fns[gf->type].flenfn(cs, gf);
+ case TARGET_SYS_TMPNAM:
+ GET_ARG(0);
+ GET_ARG(1);
+ GET_ARG(2);
+ if (asprintf(&s, "/tmp/qemu-%x%02x", getpid(),
+ (int) (arg1 & 0xff)) < 0) {
+ return -1;
+ }
+ ul_ret = (target_ulong) -1;
+
+ /* Make sure there's enough space in the buffer */
+ if (strlen(s) < arg2) {
+ char *output = lock_user(VERIFY_WRITE, arg0, arg2, 0);
+ strcpy(output, s);
+ unlock_user(output, arg0, arg2);
+ ul_ret = 0;
+ }
+ free(s);
+ return ul_ret;
+ case TARGET_SYS_REMOVE:
+ GET_ARG(0);
+ GET_ARG(1);
+ if (use_gdb_syscalls()) {
+ ret = common_semi_gdb_syscall(cs, common_semi_cb, "unlink,%s",
+ arg0, (int)arg1 + 1);
+ } else {
+ s = lock_user_string(arg0);
+ if (!s) {
+ errno = EFAULT;
+ return set_swi_errno(cs, -1);
+ }
+ ret = set_swi_errno(cs, remove(s));
+ unlock_user(s, arg0, 0);
+ }
+ return ret;
+ case TARGET_SYS_RENAME:
+ GET_ARG(0);
+ GET_ARG(1);
+ GET_ARG(2);
+ GET_ARG(3);
+ if (use_gdb_syscalls()) {
+ return common_semi_gdb_syscall(cs, common_semi_cb, "rename,%s,%s",
+ arg0, (int)arg1 + 1, arg2,
+ (int)arg3 + 1);
+ } else {
+ char *s2;
+ s = lock_user_string(arg0);
+ s2 = lock_user_string(arg2);
+ if (!s || !s2) {
+ errno = EFAULT;
+ ret = set_swi_errno(cs, -1);
+ } else {
+ ret = set_swi_errno(cs, rename(s, s2));
+ }
+ if (s2)
+ unlock_user(s2, arg2, 0);
+ if (s)
+ unlock_user(s, arg0, 0);
+ return ret;
+ }
+ case TARGET_SYS_CLOCK:
+ return clock() / (CLOCKS_PER_SEC / 100);
+ case TARGET_SYS_TIME:
+ return set_swi_errno(cs, time(NULL));
+ case TARGET_SYS_SYSTEM:
+ GET_ARG(0);
+ GET_ARG(1);
+ if (use_gdb_syscalls()) {
+ return common_semi_gdb_syscall(cs, common_semi_cb, "system,%s",
+ arg0, (int)arg1 + 1);
+ } else {
+ s = lock_user_string(arg0);
+ if (!s) {
+ errno = EFAULT;
+ return set_swi_errno(cs, -1);
+ }
+ ret = set_swi_errno(cs, system(s));
+ unlock_user(s, arg0, 0);
+ return ret;
+ }
+ case TARGET_SYS_ERRNO:
+ return get_swi_errno(cs);
+ 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->arg_end - ts->info->arg_start;
+ 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. */
+ errno = E2BIG;
+ return set_swi_errno(cs, -1);
+ }
+
+ /* Adjust the command-line length. */
+ if (SET_ARG(1, output_size - 1)) {
+ /* Couldn't write back to argument block */
+ errno = EFAULT;
+ return set_swi_errno(cs, -1);
+ }
+
+ /* Lock the buffer on the ARM side. */
+ output_buffer = lock_user(VERIFY_WRITE, arg0, output_size, 0);
+ if (!output_buffer) {
+ errno = EFAULT;
+ return set_swi_errno(cs, -1);
+ }
+
+ /* 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_start,
+ output_size)) {
+ errno = EFAULT;
+ status = set_swi_errno(cs, -1);
+ goto out;
+ }
+
+ /* 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);
+
+ return status;
+ }
+ case TARGET_SYS_HEAPINFO:
+ {
+ target_ulong retvals[4];
+ target_ulong limit;
+ int i;
+#ifdef CONFIG_USER_ONLY
+ TaskState *ts = cs->opaque;
+#else
+ target_ulong rambase = common_semi_rambase(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);
+ 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
+ limit = current_machine->ram_size;
+ /* TODO: Make this use the limit of the loaded application. */
+ retvals[0] = rambase + limit / 2;
+ retvals[1] = rambase + limit;
+ retvals[2] = rambase + limit; /* Stack base */
+ retvals[3] = rambase; /* Stack limit. */
+#endif
+
+ for (i = 0; i < ARRAY_SIZE(retvals); i++) {
+ bool fail;
+
+ fail = SET_ARG(i, retvals[i]);
+
+ if (fail) {
+ /* Couldn't write back to argument block */
+ errno = EFAULT;
+ return set_swi_errno(cs, -1);
+ }
+ }
+ return 0;
+ }
+ case TARGET_SYS_EXIT:
+ case TARGET_SYS_EXIT_EXTENDED:
+ 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) {
+ SET_ARG(0, elapsed);
+ } else {
+ SET_ARG(0, (uint32_t) elapsed);
+ SET_ARG(1, (uint32_t) (elapsed >> 32));
+ }
+ return 0;
+ case TARGET_SYS_TICKFREQ:
+ /* qemu always uses nsec */
+ return 1000000000;
+ 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.
+ */
+#ifdef TARGET_ARM
+ if (is_a64(cs->env_ptr)) {
+ return 0;
+ }
+#endif
+#ifdef TARGET_RISCV
+ return 0;
+#endif
+ /* fall through -- invalid for A32/T32 */
+ default:
+ fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);
+ cpu_dump_state(cs, stderr, 0);
+ abort();
+ }
+}