[Qemu-devel] [PATCH 2/2] linux-user: Implement prlimit64 syscall

[Peter Maydell]

Implement the prlimit64 syscall.

Signed-off-by: Peter Maydell <address@hidden>
---
 linux-user/syscall.c      |   43 +++++++++++++++++++++++++++++++++++++++++++
 linux-user/syscall_defs.h |    5 +++++
 2 files changed, 48 insertions(+), 0 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 5cb27c7..2ec1c2b 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -550,6 +550,21 @@ _syscall5(int, sys_ppoll, struct pollfd *, fds, nfds_t, 
nfds,
           size_t, sigsetsize)
 #endif
 
+#if defined(TARGET_NR_prlimit64)
+#ifndef __NR_prlimit64
+# define __NR_prlimit64 -1
+#endif
+#define __NR_sys_prlimit64 __NR_prlimit64
+/* The glibc rlimit structure may not be that used by the underlying syscall */
+struct host_rlimit64 {
+    uint64_t rlim_cur;
+    uint64_t rlim_max;
+};
+_syscall4(int, sys_prlimit64, pid_t, pid, int, resource,
+          const struct host_rlimit64 *, new_limit,
+          struct host_rlimit64 *, old_limit)
+#endif
+
 extern int personality(int);
 extern int flock(int, int);
 extern int setfsuid(int);
@@ -7840,6 +7855,34 @@ abi_long do_syscall(void *cpu_env, int num, abi_long 
arg1,
     }
 #endif
 #endif
+#ifdef TARGET_NR_prlimit64
+    case TARGET_NR_prlimit64:
+    {
+        /* args: pid, resource number, ptr to new rlimit, ptr to old rlimit */
+        struct target_rlimit64 *target_rnew, *target_rold;
+        struct host_rlimit64 rnew, rold, *rnewp = 0;
+        if (arg3) {
+            if (!lock_user_struct(VERIFY_READ, target_rnew, arg3, 1)) {
+                goto efault;
+            }
+            rnew.rlim_cur = tswap64(target_rnew->rlim_cur);
+            rnew.rlim_max = tswap64(target_rnew->rlim_max);
+            unlock_user_struct(target_rnew, arg3, 0);
+            rnewp = &rnew;
+        }
+
+        ret = get_errno(sys_prlimit64(arg1, arg2, rnewp, arg4 ? &rold : 0));
+        if (!is_error(ret) && arg4) {
+            if (!lock_user_struct(VERIFY_WRITE, target_rold, arg4, 1)) {
+                goto efault;
+            }
+            target_rold->rlim_cur = tswap64(rold.rlim_cur);
+            target_rold->rlim_max = tswap64(rold.rlim_max);
+            unlock_user_struct(target_rold, arg4, 1);
+        }
+        break;
+    }
+#endif
     default:
     unimplemented:
         gemu_log("qemu: Unsupported syscall: %d\n", num);
diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h
index 04c268d..e2700eb 100644
--- a/linux-user/syscall_defs.h
+++ b/linux-user/syscall_defs.h
@@ -2280,3 +2280,8 @@ struct target_epoll_event {
     target_epoll_data_t data;
 };
 #endif
+
+struct target_rlimit64 {
+    uint64_t rlim_cur;
+    uint64_t rlim_max;
+};
-- 
1.7.4.1