From cc84eb813c9455e3f8b222fd884d794af9ae0e7a Mon Sep 17 00:00:00 2001
From: Brandon Potter <brandon.potter@amd.com>
Date: Thu, 15 Dec 2016 13:16:25 -0500
Subject: [PATCH] syscall_emul: implement fallocate

---
 src/arch/x86/linux/process.cc |  2 +-
 src/sim/syscall_emul.cc       | 21 +++++++++++++++++++++
 src/sim/syscall_emul.hh       |  4 ++++
 3 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/src/arch/x86/linux/process.cc b/src/arch/x86/linux/process.cc
index e5db3cb49..8eb064ae4 100644
--- a/src/arch/x86/linux/process.cc
+++ b/src/arch/x86/linux/process.cc
@@ -503,7 +503,7 @@ static SyscallDesc syscallDescs64[] = {
     /* 282 */ SyscallDesc("signalfd", unimplementedFunc),
     /* 283 */ SyscallDesc("timerfd_create", unimplementedFunc),
     /* 284 */ SyscallDesc("eventfd", unimplementedFunc),
-    /* 285 */ SyscallDesc("fallocate", unimplementedFunc),
+    /* 285 */ SyscallDesc("fallocate", fallocateFunc),
     /* 286 */ SyscallDesc("timerfd_settime", unimplementedFunc),
     /* 287 */ SyscallDesc("timerfd_gettime", unimplementedFunc),
     /* 288 */ SyscallDesc("accept4", unimplementedFunc),
diff --git a/src/sim/syscall_emul.cc b/src/sim/syscall_emul.cc
index e62a8686a..9c3f50bb3 100644
--- a/src/sim/syscall_emul.cc
+++ b/src/sim/syscall_emul.cc
@@ -934,6 +934,27 @@ cloneFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
     }
 }
 
+SyscallReturn
+fallocateFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
+              ThreadContext *tc)
+{
+    int index = 0;
+    int tgt_fd = process->getSyscallArg(tc, index);
+    int mode = process->getSyscallArg(tc, index);
+    off_t offset = process->getSyscallArg(tc, index);
+    off_t len = process->getSyscallArg(tc, index);
+
+    int sim_fd = process->getSimFD(tgt_fd);
+    if (sim_fd < 0)
+        return -EBADF;
+
+    int result = fallocate(sim_fd, mode, offset, len);
+    if (result < 0)
+        return -errno;
+
+    return 0;
+}
+
 SyscallReturn
 accessFunc(SyscallDesc *desc, int callnum, LiveProcess *p, ThreadContext *tc,
         int index)
diff --git a/src/sim/syscall_emul.hh b/src/sim/syscall_emul.hh
index bf7ec1ae7..a3ac9ed3f 100644
--- a/src/sim/syscall_emul.hh
+++ b/src/sim/syscall_emul.hh
@@ -157,6 +157,10 @@ SyscallReturn unimplementedFunc(SyscallDesc *desc, int num,
 SyscallReturn ignoreFunc(SyscallDesc *desc, int num,
                          LiveProcess *p, ThreadContext *tc);
 
+// Target fallocateFunc() handler.
+SyscallReturn fallocateFunc(SyscallDesc *desc, int num,
+                            LiveProcess *p, ThreadContext *tc);
+
 /// Target exit() handler: terminate current context.
 SyscallReturn exitFunc(SyscallDesc *desc, int num,
                        LiveProcess *p, ThreadContext *tc);
-- 
2.30.2