From: Michael Ellerman <mpe@ellerman.id.au>
To: trinity@vger.kernel.org
Subject: [PATCH 1/2] Add an IGNORE_ENOSYS flag and use it
Date: Mon, 26 May 2014 22:32:01 +1000 [thread overview]
Message-ID: <1401107522-21239-1-git-send-email-mpe@ellerman.id.au> (raw)
Some syscalls return ENOSYS depending on their arguments. We don't want
to stop calling them just because we hit one of those cases. Add a flag
to specify this behaviour so we don't have to keep special-casing those
calls in mkcall().
---
include/syscall.h | 1 +
syscall.c | 23 ++++++-----------------
syscalls/futex.c | 2 +-
syscalls/ioctl.c | 2 +-
syscalls/sendfile.c | 4 ++--
5 files changed, 11 insertions(+), 21 deletions(-)
diff --git a/include/syscall.h b/include/syscall.h
index e42cd85..bc19273 100644
--- a/include/syscall.h
+++ b/include/syscall.h
@@ -121,4 +121,5 @@ struct syscalltable {
#define TO_BE_DEACTIVATED (1<<4)
#define NEED_ALARM (1<<5)
#define EXTRA_FORK (1<<6)
+#define IGNORE_ENOSYS (1<<7)
diff --git a/syscall.c b/syscall.c
index bca2aea..50e64ac 100644
--- a/syscall.c
+++ b/syscall.c
@@ -176,29 +176,18 @@ bool mkcall(int childno)
if (dopause == TRUE)
sleep(1);
- /* If the syscall doesn't exist don't bother calling it next time. */
- if ((ret == -1UL) && (errno_saved == ENOSYS)) {
-
- /* Futex is awesome, it ENOSYS's depending on arguments. Sigh. */
- if (call == (unsigned int) search_syscall_table(syscalls, max_nr_syscalls, "futex"))
- goto skip_enosys;
-
- /* Unknown ioctls also ENOSYS. */
- if (call == (unsigned int) search_syscall_table(syscalls, max_nr_syscalls, "ioctl"))
- goto skip_enosys;
-
- /* sendfile() may ENOSYS depending on args. */
- if (call == (unsigned int) search_syscall_table(syscalls, max_nr_syscalls, "sendfile"))
- goto skip_enosys;
-
+ /*
+ * If the syscall doesn't exist don't bother calling it next time.
+ * Some syscalls return ENOSYS depending on their arguments, we mark
+ * those as IGNORE_ENOSYS and keep calling them.
+ */
+ if ((ret == -1UL) && (errno_saved == ENOSYS) && !(entry->flags & IGNORE_ENOSYS)) {
output(1, "%s (%d) returned ENOSYS, marking as inactive.\n",
entry->name, call + SYSCALL_OFFSET);
deactivate_syscall(call, syscallrec->do32bit);
}
-skip_enosys:
-
if (entry->post)
entry->post(childno, syscallrec);
diff --git a/syscalls/futex.c b/syscalls/futex.c
index 5e194ab..4d18f30 100644
--- a/syscalls/futex.c
+++ b/syscalls/futex.c
@@ -33,5 +33,5 @@ struct syscallentry syscall_futex = {
.arg5type = ARG_ADDRESS,
.arg6name = "val3",
.rettype = RET_FD, // FIXME: Needs to mutate depending on 'op' value
- .flags = NEED_ALARM,
+ .flags = NEED_ALARM | IGNORE_ENOSYS,
};
diff --git a/syscalls/ioctl.c b/syscalls/ioctl.c
index 012f055..db3b485 100644
--- a/syscalls/ioctl.c
+++ b/syscalls/ioctl.c
@@ -70,5 +70,5 @@ struct syscallentry syscall_ioctl = {
.arg3name = "arg",
.arg3type = ARG_RANDPAGE,
.sanitise = sanitise_ioctl,
- .flags = NEED_ALARM,
+ .flags = NEED_ALARM | IGNORE_ENOSYS,
};
diff --git a/syscalls/sendfile.c b/syscalls/sendfile.c
index 05e49e9..3e74841 100644
--- a/syscalls/sendfile.c
+++ b/syscalls/sendfile.c
@@ -14,7 +14,7 @@ struct syscallentry syscall_sendfile = {
.arg3type = ARG_ADDRESS,
.arg4name = "count",
.arg4type = ARG_LEN,
- .flags = NEED_ALARM,
+ .flags = NEED_ALARM | IGNORE_ENOSYS,
};
/*
@@ -32,5 +32,5 @@ struct syscallentry syscall_sendfile64 = {
.arg3type = ARG_ADDRESS,
.arg4name = "count",
.arg4type = ARG_LEN,
- .flags = NEED_ALARM,
+ .flags = NEED_ALARM | IGNORE_ENOSYS,
};
--
1.9.1
next reply other threads:[~2014-05-26 12:32 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-26 12:32 Michael Ellerman [this message]
2014-05-26 12:32 ` [PATCH 2/2] Mark perf_event_open() with IGNORE_ENOSYS Michael Ellerman
2014-05-27 0:41 ` [PATCH 1/2] Add an IGNORE_ENOSYS flag and use it Dave Jones
2014-05-27 1:05 ` Michael Ellerman
2014-05-27 5:02 ` Vince Weaver
2014-05-28 3:27 ` Michael Ellerman
2014-05-28 15:38 ` Vince Weaver
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