[hurd, commited 5/6] hurd: Make write and pwrite64 cancellation points
Samuel Thibault
samuel.thibault@ens-lyon.org
Sun Jun 14 16:57:56 GMT 2020
and add _nocancel variants.
* sysdeps/mach/hurd/write.c (__libc_write): Call __write_nocancel
surrounded by enabling async cancel, to replace implementation moved
to...
* sysdeps/mach/hurd/write_nocancel.c (__write_nocancel): ... here.
* sysdeps/mach/hurd/pwrite64.c (__libc_pwrite64): Call
__pwrite64_nocancel surrounded by enabling async cancel, to replace
implementation moved to...
* sysdeps/mach/hurd/pwrite64_nocancel.c (__pwrite64_nocancel): ... here.
* sysdeps/mach/hurd/Makefile (sysdep_routines): Add write_nocancel and
pwrite64_nocancel.
* sysdeps/mach/hurd/not-cancel.h (__write_nocancel,
__pwrite64_nocancel): Replace macros with prototypes with a hidden proto on
libc.
* sysdeps/mach/hurd/dl-sysdep.c (__write_nocancel): New alias, check
that it is not hidden.
* sysdeps/mach/hurd/Versions (libc.GLIBC_PRIVATE): Add __write_nocancel.
(ld.GLIBC_PRIVATE): Add __write_nocancel.
* sysdeps/mach/hurd/i386/localplt.data (__write_nocancel): Add
reference.
---
sysdeps/mach/hurd/Makefile | 2 +-
sysdeps/mach/hurd/Versions | 2 ++
sysdeps/mach/hurd/dl-sysdep.c | 2 ++
sysdeps/mach/hurd/i386/localplt.data | 3 ++-
sysdeps/mach/hurd/not-cancel.h | 10 ++++++--
sysdeps/mach/hurd/pwrite64.c | 16 ++++++------
sysdeps/mach/hurd/pwrite64_nocancel.c | 35 +++++++++++++++++++++++++++
sysdeps/mach/hurd/write.c | 13 +++++-----
sysdeps/mach/hurd/write_nocancel.c | 30 +++++++++++++++++++++++
9 files changed, 94 insertions(+), 19 deletions(-)
create mode 100644 sysdeps/mach/hurd/pwrite64_nocancel.c
create mode 100644 sysdeps/mach/hurd/write_nocancel.c
diff --git a/sysdeps/mach/hurd/Makefile b/sysdeps/mach/hurd/Makefile
index bf741058f5..8b74d3f002 100644
--- a/sysdeps/mach/hurd/Makefile
+++ b/sysdeps/mach/hurd/Makefile
@@ -197,7 +197,7 @@ endif
ifeq (io, $(subdir))
sysdep_routines += f_setlk close_nocancel_nostatus read_nocancel \
- pread64_nocancel
+ pread64_nocancel write_nocancel pwrite64_nocancel
endif
ifeq ($(subdir),sunrpc)
diff --git a/sysdeps/mach/hurd/Versions b/sysdeps/mach/hurd/Versions
index ce873f33f6..d93ad1264e 100644
--- a/sysdeps/mach/hurd/Versions
+++ b/sysdeps/mach/hurd/Versions
@@ -11,6 +11,7 @@ libc {
# Functions shared with the dynamic linker
__access; __access_noerrno; __libc_read; __libc_write; __libc_lseek64;
__read_nocancel; __pread64_nocancel;
+ __write_nocancel;
__libc_lock_self0; __getcwd;
_dl_init_first;
@@ -51,6 +52,7 @@ ld {
# functions that must be shared with libc
__access; __access_noerrno; __libc_read; __libc_write; __libc_lseek64;
__read_nocancel; __pread64_nocancel;
+ __write_nocancel;
__libc_lock_self0; __getcwd;
}
}
diff --git a/sysdeps/mach/hurd/dl-sysdep.c b/sysdeps/mach/hurd/dl-sysdep.c
index 1626cd5928..a4eab4c08e 100644
--- a/sysdeps/mach/hurd/dl-sysdep.c
+++ b/sysdeps/mach/hurd/dl-sysdep.c
@@ -396,6 +396,7 @@ libc_hidden_weak (__read)
weak_alias (__read, __read_nocancel)
check_no_hidden(__write);
+check_no_hidden(__write_nocancel);
__ssize_t weak_function
__write (int fd, const void *buf, size_t nbytes)
{
@@ -411,6 +412,7 @@ __write (int fd, const void *buf, size_t nbytes)
return nwrote;
}
libc_hidden_weak (__write)
+ weak_alias (__write, __write_nocancel)
/* This is only used for printing messages (see dl-misc.c). */
check_no_hidden(__writev);
diff --git a/sysdeps/mach/hurd/i386/localplt.data b/sysdeps/mach/hurd/i386/localplt.data
index c9f3ca66f9..66478dee7a 100644
--- a/sysdeps/mach/hurd/i386/localplt.data
+++ b/sysdeps/mach/hurd/i386/localplt.data
@@ -23,7 +23,8 @@ ld.so: __read ?
ld.so: __read_nocancel
ld.so: __pread64
ld.so: __pread64_nocancel
-ld.so: __write
+ld.so: __write ?
+ld.so: __write_nocancel
ld.so: __writev
ld.so: __libc_lseek64
ld.so: __mmap
diff --git a/sysdeps/mach/hurd/not-cancel.h b/sysdeps/mach/hurd/not-cancel.h
index 8a8f5a9d3c..d2c3e20019 100644
--- a/sysdeps/mach/hurd/not-cancel.h
+++ b/sysdeps/mach/hurd/not-cancel.h
@@ -48,8 +48,12 @@ __typeof (__read) __read_nocancel;
/* Non cancellable pread syscall (LFS version). */
__typeof (__pread64) __pread64_nocancel;
-#define __write_nocancel(fd, buf, n) \
- __write (fd, buf, n)
+/* Non cancellable write syscall. */
+__typeof (__write) __write_nocancel;
+
+/* Non cancellable pwrite syscall (LFS version). */
+__typeof (__pwrite64) __pwrite64_nocancel;
+
#define __writev_nocancel_nostatus(fd, iov, n) \
(void) __writev (fd, iov, n)
# define __waitpid_nocancel(pid, stat_loc, options) \
@@ -60,6 +64,8 @@ __typeof (__pread64) __pread64_nocancel;
#if IS_IN (libc)
hidden_proto (__read_nocancel)
hidden_proto (__pread64_nocancel)
+hidden_proto (__write_nocancel)
+hidden_proto (__pwrite64_nocancel)
hidden_proto (__close_nocancel_nostatus)
#endif
diff --git a/sysdeps/mach/hurd/pwrite64.c b/sysdeps/mach/hurd/pwrite64.c
index d4f3a83982..961b231394 100644
--- a/sysdeps/mach/hurd/pwrite64.c
+++ b/sysdeps/mach/hurd/pwrite64.c
@@ -17,19 +17,17 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <errno.h>
-#include <unistd.h>
-#include <hurd/fd.h>
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
ssize_t
__libc_pwrite64 (int fd, const void *buf, size_t nbytes, off64_t offset)
{
- error_t err;
- if (offset < 0)
- err = EINVAL;
- else
- err = HURD_FD_USE (fd, _hurd_fd_write (descriptor, buf, &nbytes, offset));
- return err ? __hurd_dfail (fd, err) : nbytes;
+ ssize_t ret;
+ int cancel_oldtype = LIBC_CANCEL_ASYNC();
+ ret = __pwrite64_nocancel (fd, buf, nbytes, offset);
+ LIBC_CANCEL_RESET (cancel_oldtype);
+ return ret;
}
#ifndef __libc_pwrite64
diff --git a/sysdeps/mach/hurd/pwrite64_nocancel.c b/sysdeps/mach/hurd/pwrite64_nocancel.c
new file mode 100644
index 0000000000..f6bdbbe0b1
--- /dev/null
+++ b/sysdeps/mach/hurd/pwrite64_nocancel.c
@@ -0,0 +1,35 @@
+/* Write block to given position in file without changing file pointer.
+ Hurd version.
+ Copyright (C) 2001-2020 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <unistd.h>
+#include <hurd/fd.h>
+#include <not-cancel.h>
+
+ssize_t
+__pwrite64_nocancel (int fd, const void *buf, size_t nbytes, off64_t offset)
+{
+ error_t err;
+ if (offset < 0)
+ err = EINVAL;
+ else
+ err = HURD_FD_USE (fd, _hurd_fd_write (descriptor, buf, &nbytes, offset));
+ return err ? __hurd_dfail (fd, err) : nbytes;
+}
+libc_hidden_weak (__pwrite64_nocancel)
diff --git a/sysdeps/mach/hurd/write.c b/sysdeps/mach/hurd/write.c
index 9e1ade8801..0eea22be4b 100644
--- a/sysdeps/mach/hurd/write.c
+++ b/sysdeps/mach/hurd/write.c
@@ -15,16 +15,17 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <errno.h>
-#include <unistd.h>
-#include <hurd/fd.h>
+#include <sysdep-cancel.h>
+#include <not-cancel.h>
ssize_t
__libc_write (int fd, const void *buf, size_t nbytes)
{
- error_t err = HURD_FD_USE (fd, _hurd_fd_write (descriptor,
- buf, &nbytes, -1));
- return err ? __hurd_dfail (fd, err) : nbytes;
+ ssize_t ret;
+ int cancel_oldtype = LIBC_CANCEL_ASYNC();
+ ret = __write_nocancel (fd, buf, nbytes);
+ LIBC_CANCEL_RESET (cancel_oldtype);
+ return ret;
}
libc_hidden_def (__libc_write)
weak_alias (__libc_write, __write)
diff --git a/sysdeps/mach/hurd/write_nocancel.c b/sysdeps/mach/hurd/write_nocancel.c
new file mode 100644
index 0000000000..ab11c9cdd1
--- /dev/null
+++ b/sysdeps/mach/hurd/write_nocancel.c
@@ -0,0 +1,30 @@
+/* Copyright (C) 1991-2020 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <errno.h>
+#include <unistd.h>
+#include <hurd/fd.h>
+#include <not-cancel.h>
+
+ssize_t
+__write_nocancel (int fd, const void *buf, size_t nbytes)
+{
+ error_t err = HURD_FD_USE (fd, _hurd_fd_write (descriptor,
+ buf, &nbytes, -1));
+ return err ? __hurd_dfail (fd, err) : nbytes;
+}
+libc_hidden_weak (__write_nocancel)
--
2.27.0
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