Re: [Qemu-devel] [PATCH v3] linux-user/syscall.c: Handle SH4's exceptional alignment for p{read, write}64

[Riku Voipio <riku.voipio@iki.fi>]

On Wed, Oct 04, 2017 at 10:38:50AM +0200, John Paul Adrian Glaubitz wrote:
> Hi!
> 
> Any chance that this patch gets merged soon?
> 
> Looks like it has been reviewed by at least Richard and Philippe.

Sorry, slipped under radar. Applied to linux-user.
 
> Adrian
> 
> On 09/15/2017 09:33 PM, James Clarke wrote:
> >Fixes: https://bugs.launchpad.net/qemu/+bug/1716767
> >Signed-off-by: James Clarke <jrtc27@jrtc27.com>
> >---
> >
> >Changes since v2:
> >  * Fixed opening curly brace formatting, both for my new SH4-specific
> >    regpairs_aligned function, as well as the Arm one I touched, to appease
> >    checkpatch.pl
> >
> >Changes since v1:
> >  * Removed all changes in v1 :)
> >  * Added syscall num argument to regpairs_aligned
> >  * Added SH4-specific implementation of regpairs_aligned to return 1 for
> >    p{read,write}64
> >
> >  linux-user/syscall.c | 36 +++++++++++++++++++++++++-----------
> >  1 file changed, 25 insertions(+), 11 deletions(-)
> >
> >diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> >index 9b6364a266..0c1bd80bed 100644
> >--- a/linux-user/syscall.c
> >+++ b/linux-user/syscall.c
> >@@ -667,18 +667,32 @@ static inline int next_free_host_timer(void)
> >  /* ARM EABI and MIPS expect 64bit types aligned even on pairs or registers */
> >  #ifdef TARGET_ARM
> >-static inline int regpairs_aligned(void *cpu_env) {
> >+static inline int regpairs_aligned(void *cpu_env, int num)
> >+{
> >      return ((((CPUARMState *)cpu_env)->eabi) == 1) ;
> >  }
> >  #elif defined(TARGET_MIPS) && (TARGET_ABI_BITS == 32)
> >-static inline int regpairs_aligned(void *cpu_env) { return 1; }
> >+static inline int regpairs_aligned(void *cpu_env, int num) { return 1; }
> >  #elif defined(TARGET_PPC) && !defined(TARGET_PPC64)
> >  /* SysV AVI for PPC32 expects 64bit parameters to be passed on odd/even pairs
> >   * of registers which translates to the same as ARM/MIPS, because we start with
> >   * r3 as arg1 */
> >-static inline int regpairs_aligned(void *cpu_env) { return 1; }
> >+static inline int regpairs_aligned(void *cpu_env, int num) { return 1; }
> >+#elif defined(TARGET_SH4)
> >+/* SH4 doesn't align register pairs, except for p{read,write}64 */
> >+static inline int regpairs_aligned(void *cpu_env, int num)
> >+{
> >+    switch (num) {
> >+    case TARGET_NR_pread64:
> >+    case TARGET_NR_pwrite64:
> >+        return 1;
> >+
> >+    default:
> >+        return 0;
> >+    }
> >+}
> >  #else
> >-static inline int regpairs_aligned(void *cpu_env) { return 0; }
> >+static inline int regpairs_aligned(void *cpu_env, int num) { return 0; }
> >  #endif
> >  #define ERRNO_TABLE_SIZE 1200
> >@@ -6857,7 +6871,7 @@ static inline abi_long target_truncate64(void *cpu_env, const char *arg1,
> >                                           abi_long arg3,
> >                                           abi_long arg4)
> >  {
> >-    if (regpairs_aligned(cpu_env)) {
> >+    if (regpairs_aligned(cpu_env, TARGET_NR_truncate64)) {
> >          arg2 = arg3;
> >          arg3 = arg4;
> >      }
> >@@ -6871,7 +6885,7 @@ static inline abi_long target_ftruncate64(void *cpu_env, abi_long arg1,
> >                                            abi_long arg3,
> >                                            abi_long arg4)
> >  {
> >-    if (regpairs_aligned(cpu_env)) {
> >+    if (regpairs_aligned(cpu_env, TARGET_NR_ftruncate64)) {
> >          arg2 = arg3;
> >          arg3 = arg4;
> >      }
> >@@ -10495,7 +10509,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
> >  #endif
> >  #ifdef TARGET_NR_pread64
> >      case TARGET_NR_pread64:
> >-        if (regpairs_aligned(cpu_env)) {
> >+        if (regpairs_aligned(cpu_env, num)) {
> >              arg4 = arg5;
> >              arg5 = arg6;
> >          }
> >@@ -10505,7 +10519,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
> >          unlock_user(p, arg2, ret);
> >          break;
> >      case TARGET_NR_pwrite64:
> >-        if (regpairs_aligned(cpu_env)) {
> >+        if (regpairs_aligned(cpu_env, num)) {
> >              arg4 = arg5;
> >              arg5 = arg6;
> >          }
> >@@ -11275,7 +11289,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
> >          arg6 = ret;
> >  #else
> >          /* 6 args: fd, offset (high, low), len (high, low), advice */
> >-        if (regpairs_aligned(cpu_env)) {
> >+        if (regpairs_aligned(cpu_env, num)) {
> >              /* offset is in (3,4), len in (5,6) and advice in 7 */
> >              arg2 = arg3;
> >              arg3 = arg4;
> >@@ -11294,7 +11308,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
> >  #ifdef TARGET_NR_fadvise64
> >      case TARGET_NR_fadvise64:
> >          /* 5 args: fd, offset (high, low), len, advice */
> >-        if (regpairs_aligned(cpu_env)) {
> >+        if (regpairs_aligned(cpu_env, num)) {
> >              /* offset is in (3,4), len in 5 and advice in 6 */
> >              arg2 = arg3;
> >              arg3 = arg4;
> >@@ -11407,7 +11421,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
> >  #ifdef TARGET_NR_readahead
> >      case TARGET_NR_readahead:
> >  #if TARGET_ABI_BITS == 32
> >-        if (regpairs_aligned(cpu_env)) {
> >+        if (regpairs_aligned(cpu_env, num)) {
> >              arg2 = arg3;
> >              arg3 = arg4;
> >              arg4 = arg5;
> >
> 
> -- 
>  .''`.  John Paul Adrian Glaubitz
> : :' :  Debian Developer - glaubitz@debian.org
> `. `'   Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
>   `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913
>