Commit a90f590a authored by Dominik Brodowski's avatar Dominik Brodowski
Browse files

mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff() 

Using this helper allows us to avoid the in-kernel calls to the
sys_mmap_pgoff() syscall. 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_mmap_pgoff().

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: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mm@kvack.org
Signed-off-by: default avatarDominik Brodowski <linux@dominikbrodowski.net>
parent 9d5b7c95

arch/alpha/kernel/osf_sys.c

+1 −1
Original line number Diff line number Diff line
@@ -189,7 +189,7 @@ SYSCALL_DEFINE6(osf_mmap, unsigned long, addr, unsigned long, len, 
		goto out;

	if (off & ~PAGE_MASK)

		goto out;

	ret = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);

	ret = ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);

 out:

	return ret;

}

arch/arm64/kernel/sys.c

+1 −1
Original line number Diff line number Diff line
@@ -34,7 +34,7 @@ asmlinkage long sys_mmap(unsigned long addr, unsigned long len, 
	if (offset_in_page(off) != 0)

		return -EINVAL;



	return sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);

	return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);

}



SYSCALL_DEFINE1(arm64_personality, unsigned int, personality)

arch/ia64/kernel/sys_ia64.c

+2 −2
Original line number Diff line number Diff line
@@ -139,7 +139,7 @@ int ia64_mmap_check(unsigned long addr, unsigned long len, 
asmlinkage unsigned long

sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)

{

	addr = sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);

	addr = ksys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);

	if (!IS_ERR((void *) addr))

		force_successful_syscall_return();

	return addr;
@@ -151,7 +151,7 @@ sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, lo 
	if (offset_in_page(off) != 0)

		return -EINVAL;



	addr = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);

	addr = ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);

	if (!IS_ERR((void *) addr))

		force_successful_syscall_return();

	return addr;

arch/m68k/kernel/sys_m68k.c

+1 −1
Original line number Diff line number Diff line
@@ -46,7 +46,7 @@ asmlinkage long sys_mmap2(unsigned long addr, unsigned long len, 
	 * so we need to shift the argument down by 1; m68k mmap64(3)

	 * (in libc) expects the last argument of mmap2 in 4Kb units.

	 */

	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);

	return ksys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);

}



/* Convert virtual (user) address VADDR to physical address PADDR */

arch/microblaze/kernel/sys_microblaze.c

+3 −3
Original line number Diff line number Diff line
@@ -40,7 +40,7 @@ SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len, 
	if (pgoff & ~PAGE_MASK)

		return -EINVAL;



	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff >> PAGE_SHIFT);

	return ksys_mmap_pgoff(addr, len, prot, flags, fd, pgoff >> PAGE_SHIFT);

}



SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len,
@@ -50,6 +50,6 @@ SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len, 
	if (pgoff & (~PAGE_MASK >> 12))

		return -EINVAL;



	return sys_mmap_pgoff(addr, len, prot, flags, fd,

	return ksys_mmap_pgoff(addr, len, prot, flags, fd,

			       pgoff >> (PAGE_SHIFT - 12));

}

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