From fd08ddb9cb050182c0f7c9d74b11038e9c479f4f Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Sun, 14 Nov 2021 11:35:36 +0100 Subject: [PATCH] linux-user: Split out do_getdents, do_getdents64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Retain all 3 implementations of getdents for now. Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Message-Id: <20211114103539.298686-2-richard.henderson@linaro.org> Signed-off-by: Laurent Vivier --- linux-user/syscall.c | 325 +++++++++++++++++++++++-------------------- 1 file changed, 172 insertions(+), 153 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 544f5b662f..a2f605dec4 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -8137,6 +8137,176 @@ static int host_to_target_cpu_mask(const unsigned long *host_mask, return 0; } +#ifdef TARGET_NR_getdents +static int do_getdents(abi_long arg1, abi_long arg2, abi_long arg3) +{ + int ret; + +#ifdef EMULATE_GETDENTS_WITH_GETDENTS +# if TARGET_ABI_BITS == 32 && HOST_LONG_BITS == 64 + struct target_dirent *target_dirp; + struct linux_dirent *dirp; + abi_long count = arg3; + + dirp = g_try_malloc(count); + if (!dirp) { + return -TARGET_ENOMEM; + } + + ret = get_errno(sys_getdents(arg1, dirp, count)); + if (!is_error(ret)) { + struct linux_dirent *de; + struct target_dirent *tde; + int len = ret; + int reclen, treclen; + int count1, tnamelen; + + count1 = 0; + de = dirp; + target_dirp = lock_user(VERIFY_WRITE, arg2, count, 0); + if (!target_dirp) { + return -TARGET_EFAULT; + } + tde = target_dirp; + while (len > 0) { + reclen = de->d_reclen; + tnamelen = reclen - offsetof(struct linux_dirent, d_name); + assert(tnamelen >= 0); + treclen = tnamelen + offsetof(struct target_dirent, d_name); + assert(count1 + treclen <= count); + tde->d_reclen = tswap16(treclen); + tde->d_ino = tswapal(de->d_ino); + tde->d_off = tswapal(de->d_off); + memcpy(tde->d_name, de->d_name, tnamelen); + de = (struct linux_dirent *)((char *)de + reclen); + len -= reclen; + tde = (struct target_dirent *)((char *)tde + treclen); + count1 += treclen; + } + ret = count1; + unlock_user(target_dirp, arg2, ret); + } + g_free(dirp); +# else + struct linux_dirent *dirp; + abi_long count = arg3; + + dirp = lock_user(VERIFY_WRITE, arg2, count, 0); + if (!dirp) { + return -TARGET_EFAULT; + } + ret = get_errno(sys_getdents(arg1, dirp, count)); + if (!is_error(ret)) { + struct linux_dirent *de; + int len = ret; + int reclen; + de = dirp; + while (len > 0) { + reclen = de->d_reclen; + if (reclen > len) { + break; + } + de->d_reclen = tswap16(reclen); + tswapls(&de->d_ino); + tswapls(&de->d_off); + de = (struct linux_dirent *)((char *)de + reclen); + len -= reclen; + } + } + unlock_user(dirp, arg2, ret); +# endif +#else + /* Implement getdents in terms of getdents64 */ + struct linux_dirent64 *dirp; + abi_long count = arg3; + + dirp = lock_user(VERIFY_WRITE, arg2, count, 0); + if (!dirp) { + return -TARGET_EFAULT; + } + ret = get_errno(sys_getdents64(arg1, dirp, count)); + if (!is_error(ret)) { + /* + * Convert the dirent64 structs to target dirent. We do this + * in-place, since we can guarantee that a target_dirent is no + * larger than a dirent64; however this means we have to be + * careful to read everything before writing in the new format. + */ + struct linux_dirent64 *de; + struct target_dirent *tde; + int len = ret; + int tlen = 0; + + de = dirp; + tde = (struct target_dirent *)dirp; + while (len > 0) { + int namelen, treclen; + int reclen = de->d_reclen; + uint64_t ino = de->d_ino; + int64_t off = de->d_off; + uint8_t type = de->d_type; + + namelen = strlen(de->d_name); + treclen = offsetof(struct target_dirent, d_name) + namelen + 2; + treclen = QEMU_ALIGN_UP(treclen, sizeof(abi_long)); + + memmove(tde->d_name, de->d_name, namelen + 1); + tde->d_ino = tswapal(ino); + tde->d_off = tswapal(off); + tde->d_reclen = tswap16(treclen); + /* + * The target_dirent type is in what was formerly a padding + * byte at the end of the structure: + */ + *(((char *)tde) + treclen - 1) = type; + + de = (struct linux_dirent64 *)((char *)de + reclen); + tde = (struct target_dirent *)((char *)tde + treclen); + len -= reclen; + tlen += treclen; + } + ret = tlen; + } + unlock_user(dirp, arg2, ret); +#endif + return ret; +} +#endif /* TARGET_NR_getdents */ + +#if defined(TARGET_NR_getdents64) && defined(__NR_getdents64) +static int do_getdents64(abi_long arg1, abi_long arg2, abi_long arg3) +{ + struct linux_dirent64 *dirp; + abi_long count = arg3; + int ret; + + dirp = lock_user(VERIFY_WRITE, arg2, count, 0); + if (!dirp) { + return -TARGET_EFAULT; + } + ret = get_errno(sys_getdents64(arg1, dirp, count)); + if (!is_error(ret)) { + struct linux_dirent64 *de; + int len = ret; + int reclen; + de = dirp; + while (len > 0) { + reclen = de->d_reclen; + if (reclen > len) { + break; + } + de->d_reclen = tswap16(reclen); + tswap64s((uint64_t *)&de->d_ino); + tswap64s((uint64_t *)&de->d_off); + de = (struct linux_dirent64 *)((char *)de + reclen); + len -= reclen; + } + } + unlock_user(dirp, arg2, ret); + return ret; +} +#endif /* TARGET_NR_getdents64 */ + #if defined(TARGET_NR_pivot_root) && defined(__NR_pivot_root) _syscall2(int, pivot_root, const char *, new_root, const char *, put_old) #endif @@ -10227,162 +10397,11 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1, #endif #ifdef TARGET_NR_getdents case TARGET_NR_getdents: -#ifdef EMULATE_GETDENTS_WITH_GETDENTS -#if TARGET_ABI_BITS == 32 && HOST_LONG_BITS == 64 - { - struct target_dirent *target_dirp; - struct linux_dirent *dirp; - abi_long count = arg3; - - dirp = g_try_malloc(count); - if (!dirp) { - return -TARGET_ENOMEM; - } - - ret = get_errno(sys_getdents(arg1, dirp, count)); - if (!is_error(ret)) { - struct linux_dirent *de; - struct target_dirent *tde; - int len = ret; - int reclen, treclen; - int count1, tnamelen; - - count1 = 0; - de = dirp; - if (!(target_dirp = lock_user(VERIFY_WRITE, arg2, count, 0))) - return -TARGET_EFAULT; - tde = target_dirp; - while (len > 0) { - reclen = de->d_reclen; - tnamelen = reclen - offsetof(struct linux_dirent, d_name); - assert(tnamelen >= 0); - treclen = tnamelen + offsetof(struct target_dirent, d_name); - assert(count1 + treclen <= count); - tde->d_reclen = tswap16(treclen); - tde->d_ino = tswapal(de->d_ino); - tde->d_off = tswapal(de->d_off); - memcpy(tde->d_name, de->d_name, tnamelen); - de = (struct linux_dirent *)((char *)de + reclen); - len -= reclen; - tde = (struct target_dirent *)((char *)tde + treclen); - count1 += treclen; - } - ret = count1; - unlock_user(target_dirp, arg2, ret); - } - g_free(dirp); - } -#else - { - struct linux_dirent *dirp; - abi_long count = arg3; - - if (!(dirp = lock_user(VERIFY_WRITE, arg2, count, 0))) - return -TARGET_EFAULT; - ret = get_errno(sys_getdents(arg1, dirp, count)); - if (!is_error(ret)) { - struct linux_dirent *de; - int len = ret; - int reclen; - de = dirp; - while (len > 0) { - reclen = de->d_reclen; - if (reclen > len) - break; - de->d_reclen = tswap16(reclen); - tswapls(&de->d_ino); - tswapls(&de->d_off); - de = (struct linux_dirent *)((char *)de + reclen); - len -= reclen; - } - } - unlock_user(dirp, arg2, ret); - } -#endif -#else - /* Implement getdents in terms of getdents64 */ - { - struct linux_dirent64 *dirp; - abi_long count = arg3; - - dirp = lock_user(VERIFY_WRITE, arg2, count, 0); - if (!dirp) { - return -TARGET_EFAULT; - } - ret = get_errno(sys_getdents64(arg1, dirp, count)); - if (!is_error(ret)) { - /* Convert the dirent64 structs to target dirent. We do this - * in-place, since we can guarantee that a target_dirent is no - * larger than a dirent64; however this means we have to be - * careful to read everything before writing in the new format. - */ - struct linux_dirent64 *de; - struct target_dirent *tde; - int len = ret; - int tlen = 0; - - de = dirp; - tde = (struct target_dirent *)dirp; - while (len > 0) { - int namelen, treclen; - int reclen = de->d_reclen; - uint64_t ino = de->d_ino; - int64_t off = de->d_off; - uint8_t type = de->d_type; - - namelen = strlen(de->d_name); - treclen = offsetof(struct target_dirent, d_name) - + namelen + 2; - treclen = QEMU_ALIGN_UP(treclen, sizeof(abi_long)); - - memmove(tde->d_name, de->d_name, namelen + 1); - tde->d_ino = tswapal(ino); - tde->d_off = tswapal(off); - tde->d_reclen = tswap16(treclen); - /* The target_dirent type is in what was formerly a padding - * byte at the end of the structure: - */ - *(((char *)tde) + treclen - 1) = type; - - de = (struct linux_dirent64 *)((char *)de + reclen); - tde = (struct target_dirent *)((char *)tde + treclen); - len -= reclen; - tlen += treclen; - } - ret = tlen; - } - unlock_user(dirp, arg2, ret); - } -#endif - return ret; + return do_getdents(arg1, arg2, arg3); #endif /* TARGET_NR_getdents */ #if defined(TARGET_NR_getdents64) && defined(__NR_getdents64) case TARGET_NR_getdents64: - { - struct linux_dirent64 *dirp; - abi_long count = arg3; - if (!(dirp = lock_user(VERIFY_WRITE, arg2, count, 0))) - return -TARGET_EFAULT; - ret = get_errno(sys_getdents64(arg1, dirp, count)); - if (!is_error(ret)) { - struct linux_dirent64 *de; - int len = ret; - int reclen; - de = dirp; - while (len > 0) { - reclen = de->d_reclen; - if (reclen > len) - break; - de->d_reclen = tswap16(reclen); - tswap64s((uint64_t *)&de->d_ino); - tswap64s((uint64_t *)&de->d_off); - de = (struct linux_dirent64 *)((char *)de + reclen); - len -= reclen; - } - } - unlock_user(dirp, arg2, ret); - } - return ret; + return do_getdents64(arg1, arg2, arg3); #endif /* TARGET_NR_getdents64 */ #if defined(TARGET_NR__newselect) case TARGET_NR__newselect: