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author | Philippe Mathieu-Daudé <f4bug@amsat.org> | 2021-03-05 13:54:50 +0000 |
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committer | Alex Bennée <alex.bennee@linaro.org> | 2021-03-10 15:34:12 +0000 |
commit | 8df9f0c3d7f53c5a123ebb873d1c22daec003c22 (patch) | |
tree | 623a919b6e81160a13c529ce575968e5a6dd1432 /semihosting/arm-compat-semi.c | |
parent | 6b5fe13786f2e06fce4ceb5f871dd239917105c6 (diff) | |
download | qemu-8df9f0c3d7f53c5a123ebb873d1c22daec003c22.zip qemu-8df9f0c3d7f53c5a123ebb873d1c22daec003c22.tar.gz qemu-8df9f0c3d7f53c5a123ebb873d1c22daec003c22.tar.bz2 |
semihosting: Move hw/semihosting/ -> semihosting/
With the exception of hw/core/, the hw/ directory only contains
device models used in system emulation. Semihosting is also used
by user emulation. As a generic feature, move it out of hw/ directory.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210226131356.3964782-3-f4bug@amsat.org>
Message-Id: <20210305135451.15427-3-alex.bennee@linaro.org>
Diffstat (limited to 'semihosting/arm-compat-semi.c')
-rw-r--r-- | semihosting/arm-compat-semi.c | 1306 |
1 files changed, 1306 insertions, 0 deletions
diff --git a/semihosting/arm-compat-semi.c b/semihosting/arm-compat-semi.c new file mode 100644 index 0000000..94950b6 --- /dev/null +++ b/semihosting/arm-compat-semi.c @@ -0,0 +1,1306 @@ +/* + * 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(); + } +} |