Commit 36028d5d authored by Dominik Brodowski's avatar Dominik Brodowski
Browse files

fs: add ksys_p{read,write}64() helpers; remove in-kernel calls to syscalls 

Using the ksys_p{read,write}64() wrappers allows us to get rid of
in-kernel calls to the sys_pread64() and sys_pwrite64() syscalls.
The ksys_ prefix denotes that this function is meant as a drop-in
replacement for the syscall. In particular, it uses the same calling
convention as sys_p{read,write}64().

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net



Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarDominik Brodowski <linux@dominikbrodowski.net>
parent df260e21

arch/mips/kernel/linux32.c

+2 −2
Original line number Diff line number Diff line
@@ -105,13 +105,13 @@ SYSCALL_DEFINE5(32_llseek, unsigned int, fd, unsigned int, offset_high, 
SYSCALL_DEFINE6(32_pread, unsigned long, fd, char __user *, buf, size_t, count,

	unsigned long, unused, unsigned long, a4, unsigned long, a5)

{

	return sys_pread64(fd, buf, count, merge_64(a4, a5));

	return ksys_pread64(fd, buf, count, merge_64(a4, a5));

}



SYSCALL_DEFINE6(32_pwrite, unsigned int, fd, const char __user *, buf,

	size_t, count, u32, unused, u64, a4, u64, a5)

{

	return sys_pwrite64(fd, buf, count, merge_64(a4, a5));

	return ksys_pwrite64(fd, buf, count, merge_64(a4, a5));

}



SYSCALL_DEFINE1(32_personality, unsigned long, personality)

arch/parisc/kernel/sys_parisc.c

+2 −2
Original line number Diff line number Diff line
@@ -333,13 +333,13 @@ asmlinkage long parisc_ftruncate64(unsigned int fd, 
asmlinkage ssize_t parisc_pread64(unsigned int fd, char __user *buf, size_t count,

					unsigned int high, unsigned int low)

{

	return sys_pread64(fd, buf, count, (loff_t)high << 32 | low);

	return ksys_pread64(fd, buf, count, (loff_t)high << 32 | low);

}



asmlinkage ssize_t parisc_pwrite64(unsigned int fd, const char __user *buf,

			size_t count, unsigned int high, unsigned int low)

{

	return sys_pwrite64(fd, buf, count, (loff_t)high << 32 | low);

	return ksys_pwrite64(fd, buf, count, (loff_t)high << 32 | low);

}



asmlinkage ssize_t parisc_readahead(int fd, unsigned int high, unsigned int low,

arch/powerpc/kernel/sys_ppc32.c

+2 −2
Original line number Diff line number Diff line
@@ -77,13 +77,13 @@ unsigned long compat_sys_mmap2(unsigned long addr, size_t len, 
compat_ssize_t compat_sys_pread64(unsigned int fd, char __user *ubuf, compat_size_t count,

			     u32 reg6, u32 poshi, u32 poslo)

{

	return sys_pread64(fd, ubuf, count, ((loff_t)poshi << 32) | poslo);

	return ksys_pread64(fd, ubuf, count, ((loff_t)poshi << 32) | poslo);

}



compat_ssize_t compat_sys_pwrite64(unsigned int fd, const char __user *ubuf, compat_size_t count,

			      u32 reg6, u32 poshi, u32 poslo)

{

	return sys_pwrite64(fd, ubuf, count, ((loff_t)poshi << 32) | poslo);

	return ksys_pwrite64(fd, ubuf, count, ((loff_t)poshi << 32) | poslo);

}



compat_ssize_t compat_sys_readahead(int fd, u32 r4, u32 offhi, u32 offlo, u32 count)

arch/s390/kernel/compat_linux.c

+2 −2
Original line number Diff line number Diff line
@@ -315,7 +315,7 @@ COMPAT_SYSCALL_DEFINE5(s390_pread64, unsigned int, fd, char __user *, ubuf, 
{

	if ((compat_ssize_t) count < 0)

		return -EINVAL;

	return sys_pread64(fd, ubuf, count, (unsigned long)high << 32 | low);

	return ksys_pread64(fd, ubuf, count, (unsigned long)high << 32 | low);

}



COMPAT_SYSCALL_DEFINE5(s390_pwrite64, unsigned int, fd, const char __user *, ubuf,
@@ -323,7 +323,7 @@ COMPAT_SYSCALL_DEFINE5(s390_pwrite64, unsigned int, fd, const char __user *, ubu 
{

	if ((compat_ssize_t) count < 0)

		return -EINVAL;

	return sys_pwrite64(fd, ubuf, count, (unsigned long)high << 32 | low);

	return ksys_pwrite64(fd, ubuf, count, (unsigned long)high << 32 | low);

}



COMPAT_SYSCALL_DEFINE4(s390_readahead, int, fd, u32, high, u32, low, s32, count)

arch/sh/kernel/sys_sh32.c

+2 −2
Original line number Diff line number Diff line
@@ -39,13 +39,13 @@ asmlinkage int sys_sh_pipe(void) 
asmlinkage ssize_t sys_pread_wrapper(unsigned int fd, char __user *buf,

			     size_t count, long dummy, loff_t pos)

{

	return sys_pread64(fd, buf, count, pos);

	return ksys_pread64(fd, buf, count, pos);

}



asmlinkage ssize_t sys_pwrite_wrapper(unsigned int fd, const char __user *buf,

			      size_t count, long dummy, loff_t pos)

{

	return sys_pwrite64(fd, buf, count, pos);

	return ksys_pwrite64(fd, buf, count, pos);

}



asmlinkage int sys_fadvise64_64_wrapper(int fd, u32 offset0, u32 offset1,

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