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[209.132.180.131]) by mx.google.com with ESMTPS id s22si24799303ota.170.2016.09.20.08.03.18 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 20 Sep 2016 08:03:19 -0700 (PDT) Received-SPF: pass (google.com: domain of libc-alpha-return-73359-patch=linaro.org@sourceware.org designates 209.132.180.131 as permitted sender) client-ip=209.132.180.131; Authentication-Results: mx.google.com; dkim=pass header.i=@sourceware.org; spf=pass (google.com: domain of libc-alpha-return-73359-patch=linaro.org@sourceware.org designates 209.132.180.131 as permitted sender) smtp.mailfrom=libc-alpha-return-73359-patch=linaro.org@sourceware.org; dmarc=fail (p=NONE dis=NONE) header.from=linaro.org DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:subject:date:message-id:in-reply-to :references; q=dns; s=default; b=wUtBzaYqAEAJSp902nzYzalevR4gESt O2MIvw29YjxypU7wqmTJ4nA1osfElsMdV7NIrwXIKiUrJadsKKzl9VIfiS0nx64X P8lekjEJbOkwjhcbyyv3hn/JZ6aFHhaVNdKVz03HHiL0Wr0ATD8iFv/1knNiru81 R0tXnBTdobo4= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:subject:date:message-id:in-reply-to :references; s=default; bh=2QwXLxUPRJxTT1PTuhe8d5cZz+E=; b=eFovx p+UC048yXZtYCnnIS/ZmVW82PUlWoxwynLBluFurmIY4FaW9s/nBHPuIJ0lBfFEi Ec+ywBBq/ZNzt4LcdPSLBC3QAHxNinpHLpOLjGW6N00ZfnhYRynlklsDcDnmbBi4 HGR7EThPEKrjGvYzp503c5YqLLIL1IzJW06elw= Received: (qmail 10868 invoked by alias); 20 Sep 2016 15:02:19 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 10698 invoked by uid 89); 20 Sep 2016 15:02:18 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.4 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE, RCVD_IN_SORBS_SPAM, SPF_PASS autolearn=no version=3.3.2 spammy=Strong, UD:list, simplification, Seek X-HELO: mail-yw0-f173.google.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references; bh=0aWSDsCl0m4Zd9ORjuJt0JgD6K/gK8czP3IunM6JK0s=; b=TJZa6bISSjQdxiMGVQbaLd2K4kepO+VkGucBS77vKK/BSkvsqeu8ucrc22qOKN/UAs eOLCCIecO49Lex5ENKDOAzMuXceq0N8B0Sn1ENXV4tKlESFpQc9w7JhL1NsPbkQ9d8Me V57tD0rhb0ySzpY6tNubyXlcJSWCMYndp2mUjuS65+KwvcsqnAOxuVFUFNFEDXZF5OOK VicDu12Z+CmOITvaDIZw4v05gwI16HD6epZ//QqwNsAFMZrkWkplraXo2QR8OAMFMPPb eVqf4zex/F/NHigk8Q0ta8EZTLBQ8Xhua/23MNPnMRbWgmZADjYP1kH/2PyY8idAtjBh An8g== X-Gm-Message-State: AE9vXwNP09JYZaPs962TZ3XF/l42j1vBTL7sPb18nbrZh6VzB0Ppo4kjXPCwqYIRYsN2Gz+w X-Received: by 10.13.214.145 with SMTP id y139mr23211129ywd.348.1474383725018; Tue, 20 Sep 2016 08:02:05 -0700 (PDT) From: Adhemerval Zanella To: libc-alpha@sourceware.org Subject: [PATCH v3 2/4] Consolidate lseek/lseek64/llseek implementations Date: Tue, 20 Sep 2016 12:01:52 -0300 Message-Id: <1474383714-15187-3-git-send-email-adhemerval.zanella@linaro.org> In-Reply-To: <1474383714-15187-1-git-send-email-adhemerval.zanella@linaro.org> References: <1474383714-15187-1-git-send-email-adhemerval.zanella@linaro.org> Changes from previous version: - lseek64 logic to define which syscall to use depends only of __NR__llseek and __NR_lseek avaliability (instead of relying on __OFF_T_MATCHES_OFF64_T). This is make new ports that might define __OFF_T_MATCHES_OFF64_T, but still use the __NR__llseek (such as aarch64 ilp32). - Add a guard while defining __NR__llseek only if __NR_llseek is also defined. - Rebase for new pthread compat wrappers Makefile changes. -- This patch consolidates all Linux lseek/lseek64/llseek implementation in on on sysdeps/unix/sysv/linux/lseek{64}.c. It also removes the llseek file and instead consolidate the LFS lseek implementation on lseek64.c as for other LFS symbols implementations. The general idea is: - lseek: ABIs that not define __OFF_T_MATCHES_OFF64_T will preferable use __NR__llseek if kernel supports it, otherwise they will use __NR_lseek. ABIs that defines __OFF_T_MATCHES_OFF64_T won't produce any symbol. - lseek64: ABIs with __OFF_T_MATCHES_OFF64_T will preferable use __NR_lseek (since it will use 64-bit arguments without low/high splitting) and __NR__llseek if __NR_lseek is not defined (for some ILP32 ports). - llseek: files will be removed and symbols will be aliased ot lseek64. ABI without __OFF_T_MATCHES_OFF64_T and without __NR_llseek (basically MIPS64n32 so far) are covered by building lseek with off_t as expected and lseek64 using __NR_lseek (as expected for off64_t being passed using 64-bit registers). For this consolidation I mantained the x32 assembly specific implementation because to correctly fix this it would required both the x32 fix for {INLINE,INTERNAL}_SYSCALL [1] and a wrapper to correctly subscribe it to return 64 bits instead of default 32 bits (as for times). It could a future cleanup. It is based on my previous {INTERNAL,INLINE}_SYSCALL_CALL macro [2], although it is mainly for simplification. Tested on x86_64, i686, aarch64, armhf, and powerpc64le. * nptl/Makefile (pthread-compat-wrappers): Remove llseek and add lseek64. * sysdeps/unix/sysv/linux/Makefile (sysdeps_routines): Remove llseek. * sysdeps/unix/sysv/linux/alpha/Makefile (sysdeps_routines): Likewise. * sysdeps/unix/sysv/linux/generic/sysdep.h (__NR__llseek): Define iff __NR_llseek is defined. * sysdeps/unix/sysv/linux/generic/wordsize-32/llseek.c: Remove file. * sysdeps/unix/sysv/linux/generic/wordsize-32/lseek.c: Remove file. * sysdeps/unix/sysv/linux/mips/mips64/llseek.c: Likewise. * sysdeps/unix/sysv/linux/llseek.c: Remove file. * sysdeps/unix/sysv/linux/lseek.c: New file. * sysdeps/unix/sysv/linux/lseek64.c: Add default Linux implementation. * sysdeps/unix/sysv/linux/mips/mips64/syscalls.list: Remove lseek and __libc_lseek64 from auto-generation. * sysdeps/unix/sysv/linux/wordsize-64/syscalls.list: Likewise. * sysdeps/unix/sysv/linux/x86_64/x32/lseek64.S: New file. [1] https://sourceware.org/ml/libc-alpha/2016-08/msg00443.html [2] https://sourceware.org/ml/libc-alpha/2016-08/msg00646.html --- nptl/Makefile | 2 +- sysdeps/unix/sysv/linux/Makefile | 2 +- sysdeps/unix/sysv/linux/alpha/Makefile | 2 +- sysdeps/unix/sysv/linux/generic/sysdep.h | 4 +- .../unix/sysv/linux/generic/wordsize-32/llseek.c | 46 ------------------ .../unix/sysv/linux/generic/wordsize-32/lseek.c | 38 --------------- sysdeps/unix/sysv/linux/llseek.c | 46 ------------------ sysdeps/unix/sysv/linux/lseek.c | 56 ++++++++++++++++++++++ sysdeps/unix/sysv/linux/lseek64.c | 54 ++++++++++++++++++++- sysdeps/unix/sysv/linux/mips/mips64/llseek.c | 1 - sysdeps/unix/sysv/linux/mips/mips64/syscalls.list | 2 - sysdeps/unix/sysv/linux/wordsize-64/syscalls.list | 3 -- sysdeps/unix/sysv/linux/x86_64/x32/lseek64.S | 1 + 13 files changed, 116 insertions(+), 141 deletions(-) delete mode 100644 sysdeps/unix/sysv/linux/generic/wordsize-32/llseek.c delete mode 100644 sysdeps/unix/sysv/linux/generic/wordsize-32/lseek.c delete mode 100644 sysdeps/unix/sysv/linux/llseek.c create mode 100644 sysdeps/unix/sysv/linux/lseek.c delete mode 100644 sysdeps/unix/sysv/linux/mips/mips64/llseek.c create mode 100644 sysdeps/unix/sysv/linux/x86_64/x32/lseek64.S -- 2.7.4 diff --git a/nptl/Makefile b/nptl/Makefile index e9485df..ee828fe 100644 --- a/nptl/Makefile +++ b/nptl/Makefile @@ -38,7 +38,7 @@ shared-only-routines = forward pthread-compat-wrappers = \ write read close fcntl accept \ connect recv recvfrom send \ - sendto fsync lseek llseek \ + sendto fsync lseek lseek64 \ msync nanosleep open open64 pause \ pread pread64 pwrite pwrite64 \ tcdrain wait waitpid msgrcv msgsnd \ diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile index 9a0423e..16a61cb 100644 --- a/sysdeps/unix/sysv/linux/Makefile +++ b/sysdeps/unix/sysv/linux/Makefile @@ -14,7 +14,7 @@ endif ifeq ($(subdir),misc) include $(firstword $(wildcard $(sysdirs:=/sysctl.mk))) -sysdep_routines += clone llseek umount umount2 readahead \ +sysdep_routines += clone umount umount2 readahead \ setfsuid setfsgid epoll_pwait signalfd \ eventfd eventfd_read eventfd_write prlimit \ personality diff --git a/sysdeps/unix/sysv/linux/alpha/Makefile b/sysdeps/unix/sysv/linux/alpha/Makefile index 1e858ce..45941b0 100644 --- a/sysdeps/unix/sysv/linux/alpha/Makefile +++ b/sysdeps/unix/sysv/linux/alpha/Makefile @@ -10,7 +10,7 @@ ifeq ($(subdir),misc) sysdep_headers += alpha/ptrace.h alpha/regdef.h sys/io.h sysdep_routines += ieee_get_fp_control ieee_set_fp_control \ - ioperm llseek + ioperm # Support old timeval32 entry points sysdep_routines += osf_select osf_gettimeofday osf_settimeofday \ diff --git a/sysdeps/unix/sysv/linux/generic/sysdep.h b/sysdeps/unix/sysv/linux/generic/sysdep.h index b0422ff..6d379cc 100644 --- a/sysdeps/unix/sysv/linux/generic/sysdep.h +++ b/sysdeps/unix/sysv/linux/generic/sysdep.h @@ -22,7 +22,9 @@ #include /* Provide the common name to allow more code reuse. */ -#define __NR__llseek __NR_llseek +#ifdef __NR_llseek +# define __NR__llseek __NR_llseek +#endif #if __WORDSIZE == 64 /* By defining the older names, glibc will build syscall wrappers for diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/llseek.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/llseek.c deleted file mode 100644 index 458964c..0000000 --- a/sysdeps/unix/sysv/linux/generic/wordsize-32/llseek.c +++ /dev/null @@ -1,46 +0,0 @@ -/* Copyright (C) 2011-2016 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Chris Metcalf , 2011. - - 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 - . */ - -#include -#include - -#include -#include - -/* Seek to OFFSET on FD, starting from WHENCE. */ -extern loff_t __llseek (int fd, loff_t offset, int whence); - -loff_t -__llseek (int fd, loff_t offset, int whence) -{ - loff_t retval; - - return (loff_t) (INLINE_SYSCALL (_llseek, 5, fd, (off_t) (offset >> 32), - (off_t) (offset & 0xffffffff), - &retval, whence) ?: retval); -} -weak_alias (__llseek, llseek) -strong_alias (__llseek, __libc_lseek64) -strong_alias (__llseek, __lseek64) -weak_alias (__llseek, lseek64) - -/* llseek doesn't have a prototype. Since the second parameter is a - 64bit type, this results in wrong behaviour if no prototype is - provided. */ -link_warning (llseek, "\ -the `llseek' function may be dangerous; use `lseek64' instead.") diff --git a/sysdeps/unix/sysv/linux/generic/wordsize-32/lseek.c b/sysdeps/unix/sysv/linux/generic/wordsize-32/lseek.c deleted file mode 100644 index dbf0b26..0000000 --- a/sysdeps/unix/sysv/linux/generic/wordsize-32/lseek.c +++ /dev/null @@ -1,38 +0,0 @@ -/* Copyright (C) 2011-2016 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Chris Metcalf , 2011. - - 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 - . */ - -#include -#include -#include - -#include -#include - -#include "overflow.h" - -off_t -__lseek (int fd, off_t offset, int whence) -{ - loff_t res; - int rc = INLINE_SYSCALL (_llseek, 5, fd, (off_t) (offset >> 31), - (off_t) offset, &res, whence); - return rc ?: lseek_overflow (res); -} -libc_hidden_def (__lseek) -weak_alias (__lseek, lseek) -strong_alias (__lseek, __libc_lseek) diff --git a/sysdeps/unix/sysv/linux/llseek.c b/sysdeps/unix/sysv/linux/llseek.c deleted file mode 100644 index b6f3ea5..0000000 --- a/sysdeps/unix/sysv/linux/llseek.c +++ /dev/null @@ -1,46 +0,0 @@ -/* Long-long seek operation. - Copyright (C) 1996-2016 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 - . */ - -#include -#include - -#include -#include - -/* Seek to OFFSET on FD, starting from WHENCE. */ -extern loff_t __llseek (int fd, loff_t offset, int whence); - -loff_t -__llseek (int fd, loff_t offset, int whence) -{ - loff_t retval; - - return (loff_t) (INLINE_SYSCALL (_llseek, 5, fd, (off_t) (offset >> 32), - (off_t) (offset & 0xffffffff), - &retval, whence) ?: retval); -} -weak_alias (__llseek, llseek) -strong_alias (__llseek, __libc_lseek64) -strong_alias (__llseek, __lseek64) -weak_alias (__llseek, lseek64) - -/* llseek doesn't have a prototype. Since the second parameter is a - 64bit type, this results in wrong behaviour if no prototype is - provided. */ -link_warning (llseek, "\ -the `llseek' function may be dangerous; use `lseek64' instead.") diff --git a/sysdeps/unix/sysv/linux/lseek.c b/sysdeps/unix/sysv/linux/lseek.c new file mode 100644 index 0000000..568df01 --- /dev/null +++ b/sysdeps/unix/sysv/linux/lseek.c @@ -0,0 +1,56 @@ +/* Copyright (C) 2016 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 + . */ + +#include +#include +#include +#include +#include + +#ifndef __OFF_T_MATCHES_OFF64_T + +/* Test for overflows of structures where we ask the kernel to fill them + in with standard 64-bit syscalls but return them through APIs that + only expose the low 32 bits of some fields. */ + +static inline off_t lseek_overflow (loff_t res) +{ + off_t retval = (off_t) res; + if (retval == res) + return retval; + + __set_errno (EOVERFLOW); + return (off_t) -1; +} + +off_t +__lseek (int fd, off_t offset, int whence) +{ +# ifdef __NR__llseek + loff_t res; + int rc = INLINE_SYSCALL_CALL (_llseek, fd, + (long) (((uint64_t) (offset)) >> 32), + (long) offset, &res, whence); + return rc ?: lseek_overflow (res); +# else + return INLINE_SYSCALL_CALL (lseek, fd, offset, whence); +# endif +} +libc_hidden_def (__lseek) +weak_alias (__lseek, lseek) +strong_alias (__lseek, __libc_lseek) +#endif /* __OFF_T_MATCHES_OFF64_T */ diff --git a/sysdeps/unix/sysv/linux/lseek64.c b/sysdeps/unix/sysv/linux/lseek64.c index d81e98f..7e1ff23 100644 --- a/sysdeps/unix/sysv/linux/lseek64.c +++ b/sysdeps/unix/sysv/linux/lseek64.c @@ -1 +1,53 @@ -/* We don't need a definition since the llseek function is what we need. */ +/* Copyright (C) 2016 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 + . */ + +#include +#include +#include +#include +#include + +off64_t +__lseek64 (int fd, off64_t offset, int whence) +{ +#ifdef __NR__llseek + loff_t res; + int rc = INLINE_SYSCALL_CALL (_llseek, fd, + (long) (((uint64_t) (offset)) >> 32), + (long) offset, &res, whence); + return rc ?: res; +#else + return INLINE_SYSCALL_CALL (lseek, fd, offset, whence); +#endif +} + +#ifdef __OFF_T_MATCHES_OFF64_T +weak_alias (__lseek64, lseek) +weak_alias (__lseek64, __lseek) +strong_alias (__lseek64, __libc_lseek) +libc_hidden_def (__lseek) +#endif + +strong_alias (__lseek64, __libc_lseek64) +weak_alias (__lseek64, lseek64) + +/* llseek doesn't have a prototype. Since the second parameter is a + 64bit type, this results in wrong behaviour if no prototype is + provided. */ +weak_alias (__lseek64, llseek) +link_warning (llseek, "\ +the `llseek' function may be dangerous; use `lseek64' instead.") diff --git a/sysdeps/unix/sysv/linux/mips/mips64/llseek.c b/sysdeps/unix/sysv/linux/mips/mips64/llseek.c deleted file mode 100644 index 24013a8..0000000 --- a/sysdeps/unix/sysv/linux/mips/mips64/llseek.c +++ /dev/null @@ -1 +0,0 @@ -/* lseek() is 64-bit capable already. */ diff --git a/sysdeps/unix/sysv/linux/mips/mips64/syscalls.list b/sysdeps/unix/sysv/linux/mips/mips64/syscalls.list index 66cc687..d2d851e 100644 --- a/sysdeps/unix/sysv/linux/mips/mips64/syscalls.list +++ b/sysdeps/unix/sysv/linux/mips/mips64/syscalls.list @@ -1,7 +1,5 @@ # File name Caller Syscall name Args Strong name Weak names -lseek - lseek i:iii __libc_lseek __lseek lseek __llseek llseek __libc_lseek64 __lseek64 lseek64 - ftruncate - ftruncate i:ii __ftruncate ftruncate ftruncate64 __ftruncate64 truncate - truncate i:si truncate truncate64 diff --git a/sysdeps/unix/sysv/linux/wordsize-64/syscalls.list b/sysdeps/unix/sysv/linux/wordsize-64/syscalls.list index 2eb9419..3f3569f 100644 --- a/sysdeps/unix/sysv/linux/wordsize-64/syscalls.list +++ b/sysdeps/unix/sysv/linux/wordsize-64/syscalls.list @@ -1,8 +1,5 @@ # File name Caller Syscall name # args Strong name Weak names -# Whee! 64-bit systems naturally implement llseek. -llseek EXTRA lseek i:iii __libc_lseek __lseek lseek __libc_lseek64 __llseek llseek __lseek64 lseek64 -lseek llseek - fstatfs - fstatfs i:ip __fstatfs fstatfs fstatfs64 __fstatfs64 statfs - statfs i:sp __statfs statfs statfs64 mmap - mmap b:aniiii __mmap mmap __mmap64 mmap64 diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/lseek64.S b/sysdeps/unix/sysv/linux/x86_64/x32/lseek64.S new file mode 100644 index 0000000..d81e98f --- /dev/null +++ b/sysdeps/unix/sysv/linux/x86_64/x32/lseek64.S @@ -0,0 +1 @@ +/* We don't need a definition since the llseek function is what we need. */