Commit edd5cd4a authored by David Woodhouse's avatar David Woodhouse Committed by Linus Torvalds
Browse files

Introduce fixed sys_sync_file_range2() syscall, implement on PowerPC and ARM 



Not all the world is an i386.  Many architectures need 64-bit arguments to be
aligned in suitable pairs of registers, and the original
sys_sync_file_range(int, loff_t, loff_t, int) was therefore wasting an
argument register for padding after the first integer.  Since we don't
normally have more than 6 arguments for system calls, that left no room for
the final argument on some architectures.

Fix this by introducing sys_sync_file_range2(int, int, loff_t, loff_t) which
all fits nicely.  In fact, ARM already had that, but called it
sys_arm_sync_file_range.  Move it to fs/sync.c and rename it, then implement
the needed compatibility routine.  And stop the missing syscall check from
bitching about the absence of sys_sync_file_range() if we've implemented
sys_sync_file_range2() instead.

Tested on PPC32 and with 32-bit and 64-bit userspace on PPC64.

Signed-off-by: default avatarDavid Woodhouse <dwmw2@infradead.org>
Acked-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 2f4d4da8

arch/arm/kernel/calls.S

+1 −1
Original line number Diff line number Diff line
@@ -350,7 +350,7 @@ 
		CALL(sys_set_robust_list)

		CALL(sys_get_robust_list)

/* 340 */	CALL(sys_splice)

		CALL(sys_arm_sync_file_range)

		CALL(sys_sync_file_range2)

		CALL(sys_tee)

		CALL(sys_vmsplice)

		CALL(sys_move_pages)

arch/arm/kernel/sys_arm.c

+0 −13
Original line number Diff line number Diff line
@@ -328,16 +328,3 @@ asmlinkage long sys_arm_fadvise64_64(int fd, int advice, 
{

	return sys_fadvise64_64(fd, offset, len, advice);

}
 


/*

 * Yet more syscall fsckage - we can't fit sys_sync_file_range's

 * arguments into the available registers with EABI.  So, let's

 * create an ARM specific syscall for this which has _sane_

 * arguments.  (This incidentally also has an ABI-independent

 * argument layout.)

 */

asmlinkage long sys_arm_sync_file_range(int fd, unsigned int flags,

					loff_t offset, loff_t nbytes)

{

	return sys_sync_file_range(fd, offset, nbytes, flags);

}

arch/powerpc/kernel/sys_ppc32.c

+9 −0
Original line number Diff line number Diff line
@@ -810,3 +810,12 @@ asmlinkage long compat_sys_request_key(const char __user *_type, 
	return sys_request_key(_type, _description, _callout_info, destringid);

}



asmlinkage long compat_sys_sync_file_range2(int fd, unsigned int flags,

				   unsigned offset_hi, unsigned offset_lo,

				   unsigned nbytes_hi, unsigned nbytes_lo)

{

	loff_t offset = ((loff_t)offset_hi << 32) | offset_lo;

	loff_t nbytes = ((loff_t)nbytes_hi << 32) | nbytes_lo;



	return sys_sync_file_range(fd, offset, nbytes, flags);

}

fs/sync.c

+8 −0
Original line number Diff line number Diff line
@@ -236,6 +236,14 @@ out: 
	return ret;

}



/* It would be nice if people remember that not all the world's an i386

   when they introduce new system calls */

asmlinkage long sys_sync_file_range2(int fd, unsigned int flags,

				     loff_t offset, loff_t nbytes)

{

	return sys_sync_file_range(fd, offset, nbytes, flags);

}



/*

 * `endbyte' is inclusive

 */

include/asm-arm/unistd.h

+1 −0
Original line number Diff line number Diff line
@@ -367,6 +367,7 @@ 
#define __NR_get_robust_list		(__NR_SYSCALL_BASE+339)

#define __NR_splice			(__NR_SYSCALL_BASE+340)

#define __NR_arm_sync_file_range	(__NR_SYSCALL_BASE+341)

#define __NR_sync_file_range2		__NR_arm_sync_file_range

#define __NR_tee			(__NR_SYSCALL_BASE+342)

#define __NR_vmsplice			(__NR_SYSCALL_BASE+343)

#define __NR_move_pages			(__NR_SYSCALL_BASE+344)

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