diff mbox series

[4/6] bsd-user/bsd-file.h: Add implementations for read, pread, readv and preadv

Message ID 20220607201440.41464-5-imp@bsdimp.com
State New
Headers show
Series bsd-user upstreaming: read, write and exit | expand

Commit Message

Warner Losh June 7, 2022, 8:14 p.m. UTC 
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>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
 bsd-user/bsd-file.h           | 79 +++++++++++++++++++++++++++++++++++
 bsd-user/freebsd/os-syscall.c | 24 +++++++++++
 2 files changed, 103 insertions(+)

Comments

Richard Henderson June 7, 2022, 9:45 p.m. UTC | #1 
On 6/7/22 13:14, Warner Losh wrote:
> +/* read(2) */
> +static inline abi_long do_bsd_read(abi_long arg1, abi_long arg2, abi_long arg3)

Why the inline markers?  Best to drop them.

> +        /*
> +         * 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;

Missing preadv, which you added above.

r~
Warner Losh June 8, 2022, 2:02 a.m. UTC | #2 
On Tue, Jun 7, 2022 at 2:45 PM Richard Henderson <
richard.henderson@linaro.org> wrote:

> On 6/7/22 13:14, Warner Losh wrote:
> > +/* read(2) */
> > +static inline abi_long do_bsd_read(abi_long arg1, abi_long arg2,
> abi_long arg3)
>
> Why the inline markers?  Best to drop them.
>

static inline ensures that we don't get a warning if bsd-file.h is included
in multiple places and these routines aren't used.

Though it turns out....


> > +        /*
> > +         * 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;
>
> Missing preadv, which you added above.


It would have caught this :)  I'll update this and the write changes...

Warner
diff mbox series

Patch

diff --git a/bsd-user/bsd-file.h b/bsd-user/bsd-file.h
index a6bff3b8c26..ed305439e1a 100644
--- a/bsd-user/bsd-file.h
+++ b/bsd-user/bsd-file.h
@@ -27,4 +27,83 @@  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;
+    }
+    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 334c573739b..79fb2cb69f8 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)
 {
 }
@@ -211,6 +219,22 @@  static abi_long freebsd_syscall(void *cpu_env, int num, abi_long arg1,
     abi_long ret;
 
     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;