[hurd,commited] hurd: Make fcntl(F_SETLKW*) cancellation points

Message ID 20200628200300.672945-1-samuel.thibault@ens-lyon.org
State New
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Series
  • [hurd,commited] hurd: Make fcntl(F_SETLKW*) cancellation points
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Commit Message

Samuel Thibault June 28, 2020, 8:03 p.m.
and add _nocancel variant.

* sysdeps/mach/hurd/Makefile [io] (sysdep_routines): Add fcntl_nocancel.
* sysdeps/mach/hurd/fcntl.c [NOCANCEL]: Include <not-cancel.h>.
[!NOCANCEL]: Include <sysdep-cancel.h>.
(__libc_fcntl) [!NOCANCEL]: Surround __file_record_lock call with enabling async cancel, and use HURD_FD_PORT_USE_CANCEL instead of HURD_FD_PORT_USE.
* sysdeps/mach/hurd/fcntl_nocancel.c: New file, defines __fcntl_nocancel by including fcntl.c.
* sysdeps/mach/hurd/not-cancel.h (__fcntl64_nocancel): Replace macro with
    __fcntl_nocancel declaration with hidden proto, and make
    __fcntl64_nocancel call __fcntl_nocancel.
---
 sysdeps/mach/hurd/Makefile         |  2 +-
 sysdeps/mach/hurd/fcntl.c          | 38 ++++++++++++++++++++++++++----
 sysdeps/mach/hurd/fcntl_nocancel.c |  3 +++
 sysdeps/mach/hurd/not-cancel.h     |  9 ++++---
 4 files changed, 44 insertions(+), 8 deletions(-)
 create mode 100644 sysdeps/mach/hurd/fcntl_nocancel.c

-- 
2.27.0

Patch

diff --git a/sysdeps/mach/hurd/Makefile b/sysdeps/mach/hurd/Makefile
index a1ca034175..9c53db3783 100644
--- a/sysdeps/mach/hurd/Makefile
+++ b/sysdeps/mach/hurd/Makefile
@@ -197,7 +197,7 @@  endif
 
 ifeq (io, $(subdir))
 sysdep_routines += f_setlk close_nocancel close_nocancel_nostatus \
-		   open_nocancel openat_nocancel read_nocancel \
+		   fcntl_nocancel open_nocancel openat_nocancel read_nocancel \
 		   pread64_nocancel write_nocancel pwrite64_nocancel \
 		   wait4_nocancel
 endif
diff --git a/sysdeps/mach/hurd/fcntl.c b/sysdeps/mach/hurd/fcntl.c
index 95b0ebff0f..564d9dcd23 100644
--- a/sysdeps/mach/hurd/fcntl.c
+++ b/sysdeps/mach/hurd/fcntl.c
@@ -21,6 +21,11 @@ 
 #include <hurd/fd.h>
 #include <stdarg.h>
 #include <sys/file.h>		/* XXX for LOCK_* */
+#ifdef NOCANCEL
+#include <not-cancel.h>
+#else
+#include <sysdep-cancel.h>
+#endif
 #include "f_setlk.h"
 
 /* Perform file control operations on FD.  */
@@ -155,8 +160,19 @@  __libc_fcntl (int fd, int cmd, ...)
 	  .l_pid = fl->l_pid
 	};
 
-	err = HURD_FD_PORT_USE (d, __file_record_lock (port, cmd, &fl64,
-				MACH_PORT_NULL, MACH_MSG_TYPE_MAKE_SEND));
+#ifndef NOCANCEL
+	if (cmd == F_SETLKW64)
+	  {
+	    int cancel_oldtype = LIBC_CANCEL_ASYNC();
+	    err = HURD_FD_PORT_USE_CANCEL (d, __file_record_lock (port, cmd,
+					   &fl64, MACH_PORT_NULL,
+					   MACH_MSG_TYPE_MAKE_SEND));
+	    LIBC_CANCEL_RESET (cancel_oldtype);
+	  }
+	else
+#endif
+	  err = HURD_FD_PORT_USE (d, __file_record_lock (port, cmd, &fl64,
+				  MACH_PORT_NULL, MACH_MSG_TYPE_MAKE_SEND));
 
 	/* XXX: To remove once file_record_lock RPC is settled.  */
 	if (err == EMIG_BAD_ID || err == EOPNOTSUPP)
@@ -207,8 +223,19 @@  __libc_fcntl (int fd, int cmd, ...)
       {
 	struct flock64 *fl = va_arg (ap, struct flock64 *);
 
-	err = HURD_FD_PORT_USE (d, __file_record_lock (port, cmd, fl,
-				MACH_PORT_NULL, MACH_MSG_TYPE_MAKE_SEND));
+#ifndef NOCANCEL
+	if (cmd == F_SETLKW64)
+	  {
+	    int cancel_oldtype = LIBC_CANCEL_ASYNC();
+	    err = HURD_FD_PORT_USE_CANCEL (d, __file_record_lock (port, cmd,
+					   fl, MACH_PORT_NULL,
+					   MACH_MSG_TYPE_MAKE_SEND));
+	    LIBC_CANCEL_RESET (cancel_oldtype);
+	  }
+	else
+#endif
+	  err = HURD_FD_PORT_USE (d, __file_record_lock (port, cmd, fl,
+				  MACH_PORT_NULL, MACH_MSG_TYPE_MAKE_SEND));
 
 	/* XXX: To remove once file_record_lock RPC is settled.  */
 	if (err == EMIG_BAD_ID || err == EOPNOTSUPP)
@@ -263,6 +290,8 @@  __libc_fcntl (int fd, int cmd, ...)
   return result;
 }
 libc_hidden_def (__libc_fcntl)
+
+#ifndef NOCANCEL
 weak_alias (__libc_fcntl, __fcntl)
 libc_hidden_weak (__fcntl)
 weak_alias (__libc_fcntl, fcntl)
@@ -272,3 +301,4 @@  libc_hidden_def (__libc_fcntl64)
 weak_alias (__libc_fcntl64, __fcntl64)
 libc_hidden_weak (__fcntl64)
 weak_alias (__fcntl64, fcntl64)
+#endif
diff --git a/sysdeps/mach/hurd/fcntl_nocancel.c b/sysdeps/mach/hurd/fcntl_nocancel.c
new file mode 100644
index 0000000000..8913405409
--- /dev/null
+++ b/sysdeps/mach/hurd/fcntl_nocancel.c
@@ -0,0 +1,3 @@ 
+#define NOCANCEL
+#define __libc_fcntl __fcntl_nocancel
+#include <sysdeps/mach/hurd/fcntl.c>
diff --git a/sysdeps/mach/hurd/not-cancel.h b/sysdeps/mach/hurd/not-cancel.h
index 69cd781f68..94b731c080 100644
--- a/sysdeps/mach/hurd/not-cancel.h
+++ b/sysdeps/mach/hurd/not-cancel.h
@@ -69,9 +69,11 @@  __typeof (__wait4) __wait4_nocancel;
 # define __waitpid_nocancel(pid, stat_loc, options) \
   __wait4_nocancel (pid, stat_loc, options, NULL)
 
-/* For now we have none.  Map the name to the normal functions.  */
-#define __fcntl64_nocancel(fd, cmd, ...) \
-  __fcntl64 (fd, cmd, __VA_ARGS__)
+/* Non cancellable fcntl syscall.  */
+__typeof (__fcntl) __fcntl_nocancel;
+/* fcntl64 is just the same as fcntl for us.  */
+#define __fcntl64_nocancel(...) \
+  __fcntl_nocancel (__VA_ARGS__)
 
 #if IS_IN (libc)
 hidden_proto (__close_nocancel)
@@ -85,6 +87,7 @@  hidden_proto (__pwrite64_nocancel)
 hidden_proto (__writev_nocancel)
 hidden_proto (__writev_nocancel_nostatus)
 hidden_proto (__wait4_nocancel)
+hidden_proto (__fcntl_nocancel)
 #endif
 
 #endif /* NOT_CANCEL_H  */