commit aa915bd0a67d6c0a214b45372ed841521c5cd07a
author Richard Henderson <richard.henderson@linaro.org> Thu Apr 28 11:49:47 2022 -0700
committer Richard Henderson <richard.henderson@linaro.org> Tue Jun 28 04:35:52 2022 +0530
tree b0269554631c6f481a823fdd6e55db0a1542aa0c
parent af0484b5025f8b7c951428a00b5bb3f172a2da8d

semihosting: Split out semihost_sys_write

Split out the non-ARM specific portions of SYS_WRITE to a
reusable function.  This handles all GuestFD.  This removes
the last use of common_semi_syscall_len.

Note that gdb_do_syscall %x reads target_ulong, not int.

Reviewed-by: Luc Michel <lmichel@kalray.eu>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

semihosting/arm-compat-semi.c

diff --git a/semihosting/arm-compat-semi.c b/semihosting/arm-compat-semi.c
index 8da31d8..d591fcd 100644
--- a/semihosting/arm-compat-semi.c
+++ b/semihosting/arm-compat-semi.c
@@ -215,8 +215,6 @@
 #endif
 }
 
-static target_ulong common_semi_syscall_len;
-
 static void common_semi_cb(CPUState *cs, target_ulong ret, target_ulong err)
 {
     if (err) {
@@ -230,9 +228,6 @@
         /* Fixup syscalls that use nonstardard return conventions.  */
         target_ulong reg0 = common_semi_arg(cs, 0);
         switch (reg0) {
-        case TARGET_SYS_WRITE:
-            ret = common_semi_syscall_len - ret;
-            break;
         case TARGET_SYS_SEEK:
             ret = 0;
             break;
@@ -294,30 +289,10 @@
  * do the work and return the required return value to the guest
  * via common_semi_cb.
  */
-typedef void sys_writefn(CPUState *cs, GuestFD *gf,
-                         target_ulong buf, uint32_t len);
 typedef void sys_isattyfn(CPUState *cs, GuestFD *gf);
 typedef void sys_seekfn(CPUState *cs, GuestFD *gf, target_ulong offset);
 typedef void sys_flenfn(CPUState *cs, GuestFD *gf);
 
-static void host_writefn(CPUState *cs, GuestFD *gf,
-                         target_ulong buf, uint32_t len)
-{
-    CPUArchState *env = cs->env_ptr;
-    uint32_t ret = 0;
-    char *s = lock_user(VERIFY_READ, buf, len, 1);
-    (void) env; /* Used in arm softmmu lock_user implicitly */
-    if (s) {
-        ret = write(gf->hostfd, s, len);
-        unlock_user(s, buf, 0);
-        if (ret == (uint32_t)-1) {
-            ret = 0;
-        }
-    }
-    /* Return bytes not written, on error as well. */
-    common_semi_cb(cs, len - ret, 0);
-}
-
 static void host_isattyfn(CPUState *cs, GuestFD *gf)
 {
     common_semi_cb(cs, isatty(gf->hostfd), 0);
@@ -340,13 +315,6 @@
     }
 }
 
-static void gdb_writefn(CPUState *cs, GuestFD *gf,
-                        target_ulong buf, uint32_t len)
-{
-    common_semi_syscall_len = len;
-    gdb_do_syscall(common_semi_cb, "write,%x,%x,%x", gf->hostfd, buf, len);
-}
-
 static void gdb_isattyfn(CPUState *cs, GuestFD *gf)
 {
     gdb_do_syscall(common_semi_cb, "isatty,%x", gf->hostfd);
@@ -380,13 +348,6 @@
     SH_EXT_EXIT_EXTENDED | SH_EXT_STDOUT_STDERR, /* Feature byte 0 */
 };
 
-static void staticfile_writefn(CPUState *cs, GuestFD *gf,
-                               target_ulong buf, uint32_t len)
-{
-    /* This fd can never be open for writing */
-    common_semi_cb(cs, -1, EBADF);
-}
-
 static void staticfile_isattyfn(CPUState *cs, GuestFD *gf)
 {
     common_semi_cb(cs, 0, 0);
@@ -404,7 +365,6 @@
 }
 
 typedef struct GuestFDFunctions {
-    sys_writefn *writefn;
     sys_isattyfn *isattyfn;
     sys_seekfn *seekfn;
     sys_flenfn *flenfn;
@@ -412,19 +372,16 @@
 
 static const GuestFDFunctions guestfd_fns[] = {
     [GuestFDHost] = {
-        .writefn = host_writefn,
         .isattyfn = host_isattyfn,
         .seekfn = host_seekfn,
         .flenfn = host_flenfn,
     },
     [GuestFDGDB] = {
-        .writefn = gdb_writefn,
         .isattyfn = gdb_isattyfn,
         .seekfn = gdb_seekfn,
         .flenfn = gdb_flenfn,
     },
     [GuestFDStatic] = {
-        .writefn = staticfile_writefn,
         .isattyfn = staticfile_isattyfn,
         .seekfn = staticfile_seekfn,
         .flenfn = staticfile_flenfn,
@@ -449,7 +406,6 @@
     char * s;
     int nr;
     uint32_t ret;
-    uint32_t len;
     GuestFD *gf;
     int64_t elapsed;
 
@@ -531,13 +487,7 @@
         GET_ARG(0);
         GET_ARG(1);
         GET_ARG(2);
-        len = arg2;
-
-        gf = get_guestfd(arg0);
-        if (!gf) {
-            goto do_badf;
-        }
-        guestfd_fns[gf->type].writefn(cs, gf, arg1, len);
+        semihost_sys_write(cs, common_semi_rw_cb, arg0, arg1, arg2);
         break;
 
     case TARGET_SYS_READ: