On 2/1/22 22:14, Warner Losh wrote:
> Implement do_bsd_{read,pread,readv,preadv}. Connect them to the system
> call table.
>
> Signed-off-by: Stacey Son <sson@FreeBSD.org>
> Signed-off-by: Kyle Evans <kevans@FreeBSD.org>
> Signed-off-by: Warner Losh <imp@bsdimp.com>
> ---
> bsd-user/bsd-file.h | 79 +++++++++++++++++++++++++++++++++++
> bsd-user/freebsd/os-syscall.c | 24 +++++++++++
> 2 files changed, 103 insertions(+)
>
> diff --git a/bsd-user/bsd-file.h b/bsd-user/bsd-file.h
> index 2f743db38e1..5934cbd5612 100644
> --- a/bsd-user/bsd-file.h
> +++ b/bsd-user/bsd-file.h
> @@ -36,4 +36,83 @@ extern struct iovec *lock_iovec(int type, abi_ulong target_addr, int count,
> extern void unlock_iovec(struct iovec *vec, abi_ulong target_addr, int count,
> int copy);
>
> +ssize_t safe_read(int fd, void *buf, size_t nbytes);
> +ssize_t safe_pread(int fd, void *buf, size_t nbytes, off_t offset);
> +ssize_t safe_readv(int fd, const struct iovec *iov, int iovcnt);
> +ssize_t safe_preadv(int fd, const struct iovec *iov, int iovcnt, off_t offset);
> +
> +/* read(2) */
> +static inline abi_long do_bsd_read(abi_long arg1, abi_long arg2, abi_long arg3)
> +{
> + abi_long ret;
> + void *p;
> +
> + p = lock_user(VERIFY_WRITE, arg2, arg3, 0);
> + if (p == NULL) {
> + return -TARGET_EFAULT;
> + }
> + ret = get_errno(safe_read(arg1, p, arg3));
> + unlock_user(p, arg2, ret);
> +
> + return ret;
> +}
> +
> +/* pread(2) */
> +static inline abi_long do_bsd_pread(void *cpu_env, abi_long arg1,
> + abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5, abi_long arg6)
> +{
> + abi_long ret;
> + void *p;
> +
> + p = lock_user(VERIFY_WRITE, arg2, arg3, 0);
> + if (p == NULL) {
> + return -TARGET_EFAULT;
> + }
> + if (regpairs_aligned(cpu_env) != 0) {
> + arg4 = arg5;
> + arg5 = arg6;
> + }
This would be clearer if you had started labeling from arg0.
There's a number of other changes this would force, so I'll defer
it...
Warner
But either way,
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
r~
> + ret = get_errno(safe_pread(arg1, p, arg3, target_arg64(arg4, arg5)));
> + unlock_user(p, arg2, ret);
> +
> + return ret;
> +}
> +
> +/* readv(2) */
> +static inline abi_long do_bsd_readv(abi_long arg1, abi_long arg2, abi_long arg3)
> +{
> + abi_long ret;
> + struct iovec *vec = lock_iovec(VERIFY_WRITE, arg2, arg3, 0);
> +
> + if (vec != NULL) {
> + ret = get_errno(safe_readv(arg1, vec, arg3));
> + unlock_iovec(vec, arg2, arg3, 1);
> + } else {
> + ret = -host_to_target_errno(errno);
> + }
> +
> + return ret;
> +}
> +
> +/* preadv(2) */
> +static inline abi_long do_bsd_preadv(void *cpu_env, abi_long arg1,
> + abi_long arg2, abi_long arg3, abi_long arg4, abi_long arg5, abi_long arg6)
> +{
> + abi_long ret;
> + struct iovec *vec = lock_iovec(VERIFY_WRITE, arg2, arg3, 1);
> +
> + if (vec != NULL) {
> + if (regpairs_aligned(cpu_env) != 0) {
> + arg4 = arg5;
> + arg5 = arg6;
> + }
> + ret = get_errno(safe_preadv(arg1, vec, arg3, target_arg64(arg4, arg5)));
> + unlock_iovec(vec, arg2, arg3, 0);
> + } else {
> + ret = -host_to_target_errno(errno);
> + }
> +
> + return ret;
> +}
> +
> #endif /* !BSD_FILE_H_ */
> diff --git a/bsd-user/freebsd/os-syscall.c b/bsd-user/freebsd/os-syscall.c
> index fcfa6221182..dda79af53de 100644
> --- a/bsd-user/freebsd/os-syscall.c
> +++ b/bsd-user/freebsd/os-syscall.c
> @@ -42,6 +42,14 @@
>
> #include "bsd-file.h"
>
> +/* I/O */
> +safe_syscall3(ssize_t, read, int, fd, void *, buf, size_t, nbytes);
> +safe_syscall4(ssize_t, pread, int, fd, void *, buf, size_t, nbytes, off_t,
> + offset);
> +safe_syscall3(ssize_t, readv, int, fd, const struct iovec *, iov, int, iovcnt);
> +safe_syscall4(ssize_t, preadv, int, fd, const struct iovec *, iov, int, iovcnt,
> + off_t, offset);
> +
> void target_set_brk(abi_ulong new_brk)
> {
> }
> @@ -212,6 +220,22 @@ abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1,
> }
>
> switch (num) {
> +
> + /*
> + * File system calls.
> + */
> + case TARGET_FREEBSD_NR_read: /* read(2) */
> + ret = do_bsd_read(arg1, arg2, arg3);
> + break;
> +
> + case TARGET_FREEBSD_NR_pread: /* pread(2) */
> + ret = do_bsd_pread(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6);
> + break;
> +
> + case TARGET_FREEBSD_NR_readv: /* readv(2) */
> + ret = do_bsd_readv(arg1, arg2, arg3);
> + break;
> +
> default:
> gemu_log("qemu: unsupported syscall: %d\n", num);
> ret = -TARGET_ENOSYS;