Implement 32-bit compatibility for waitid(2).

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

4 files changed, 51 insertions, 2 deletions

diff --git a/arch/mips/kernel/linux32.c b/arch/mips/kernel/linux32.c
index dfb448c015e1..120dd897162e 100644
--- a/arch/mips/kernel/linux32.c
+++ b/arch/mips/kernel/linux32.c
@@ -221,6 +221,28 @@ sys32_waitpid(compat_pid_t pid, unsigned int *stat_addr, int options)
         return compat_sys_wait4(pid, stat_addr, options, NULL);
 }
 
+asmlinkage long
+sysn32_waitid(int which, compat_pid_t pid,
+              siginfo_t __user *uinfo, int options,
+              struct compat_rusage __user *uru)
+{
+        struct rusage ru;
+        long ret;
+        mm_segment_t old_fs = get_fs();
+
+        set_fs (KERNEL_DS);
+        ret = sys_waitid(which, pid, uinfo, options,
+                         uru ? (struct rusage __user *) &ru : NULL);
+        set_fs (old_fs);
+
+        if (ret < 0 || uinfo->si_signo == 0)
+                return ret;
+
+        if (uru)
+                ret = put_compat_rusage(&ru, uru);
+        return ret;
+}
+
 struct sysinfo32 {
         s32 uptime;
         u32 loads[3];
diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S
index 3a56056d8125..982248a17393 100644
--- a/arch/mips/kernel/scall64-n32.S
+++ b/arch/mips/kernel/scall64-n32.S
@@ -358,7 +358,7 @@ EXPORT(sysn32_call_table)
         PTR     compat_sys_mq_notify
         PTR     compat_sys_mq_getsetattr
         PTR     sys_ni_syscall                  /* 6240, sys_vserver */
-        PTR     sys_waitid
+        PTR     sysn32_waitid
         PTR     sys_ni_syscall                  /* available, was setaltroot */
         PTR     sys_add_key
         PTR     sys_request_key
diff --git a/arch/mips/kernel/scall64-o32.S b/arch/mips/kernel/scall64-o32.S
index 271b2cb14da0..00e0d2b8fd8e 100644
--- a/arch/mips/kernel/scall64-o32.S
+++ b/arch/mips/kernel/scall64-o32.S
@@ -480,7 +480,7 @@ sys_call_table:
         PTR     compat_sys_mq_notify            /* 4275 */
         PTR     compat_sys_mq_getsetattr
         PTR     sys_ni_syscall                  /* sys_vserver */
-        PTR     sys_waitid
+        PTR     sys32_waitid
         PTR     sys_ni_syscall                  /* available, was setaltroot */
         PTR     sys_add_key                     /* 4280 */
         PTR     sys_request_key
diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c
index 8ddfbd8d425a..d50daee51fba 100644
--- a/arch/mips/kernel/signal32.c
+++ b/arch/mips/kernel/signal32.c
@@ -902,3 +902,30 @@ asmlinkage int sys32_rt_sigqueueinfo(int pid, int sig, compat_siginfo_t *uinfo)
         set_fs (old_fs);
         return ret;
 }
+
+asmlinkage long
+sys32_waitid(int which, compat_pid_t pid,
+             compat_siginfo_t __user *uinfo, int options,
+             struct compat_rusage __user *uru)
+{
+        siginfo_t info;
+        struct rusage ru;
+        long ret;
+        mm_segment_t old_fs = get_fs();
+
+        info.si_signo = 0;
+        set_fs (KERNEL_DS);
+        ret = sys_waitid(which, pid, (siginfo_t __user *) &info, options,
+                         uru ? (struct rusage __user *) &ru : NULL);
+        set_fs (old_fs);
+
+        if (ret < 0 || info.si_signo == 0)
+                return ret;
+
+        if (uru && (ret = put_compat_rusage(&ru, uru)))
+                return ret;
+
+        BUG_ON(info.si_code & __SI_MASK);
+        info.si_code |= __SI_CHLD;
+        return copy_siginfo_to_user32(uinfo, &info);
+}