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.

David Woodhouse committed 19 years ago

Commit edd5cd41 parent 2f4d4da9 files · +29 −15Browse files

Unified · Split

9 files

arch/arm/kernel/calls.S +1 −1
arch/arm/kernel/sys_arm.c +0 −13
arch/powerpc/kernel/sys_ppc32.c +9 −0
fs/sync.c +8 −0
include/asm-arm/unistd.h +1 −0
include/asm-powerpc/systbl.h +1 −0
include/asm-powerpc/unistd.h +2 −1
include/linux/syscalls.h +2 −0
scripts/checksyscalls.sh +5 −0

arch/arm/kernel/calls.S+1−1

@@ -350,7 +350,7 @@ · 349 unmodified lines
350	CALL(sys_set_robust_list)	350	CALL(sys_set_robust_list)
351	CALL(sys_get_robust_list)	351	CALL(sys_get_robust_list)
352	/* 340 */ CALL(sys_splice)	352	/* 340 */ CALL(sys_splice)
353	CALL(sys_arm_sync_file_range)	353	CALL(sys_sync_file_range2)
354	CALL(sys_tee)	354	CALL(sys_tee)
355	CALL(sys_vmsplice)	355	CALL(sys_vmsplice)
356	CALL(sys_move_pages)	356	CALL(sys_move_pages)

arch/arm/kernel/sys_arm.c+0−13

@@ -328,16 +328,3 @@ asmlinkage long sys_arm_fadvise64_64(int fd, int advice, · 327 unmodified lines
328	{	328	{
329	return sys_fadvise64_64(fd, offset, len, advice);	329	return sys_fadvise64_64(fd, offset, len, advice);
330	}	330	}
331
332	/*
333	* Yet more syscall fsckage - we can't fit sys_sync_file_range's
334	* arguments into the available registers with EABI. So, let's
335	* create an ARM specific syscall for this which has _sane_
336	* arguments. (This incidentally also has an ABI-independent
337	* argument layout.)
338	*/
339	asmlinkage long sys_arm_sync_file_range(int fd, unsigned int flags,
340	loff_t offset, loff_t nbytes)
341	{
342	return sys_sync_file_range(fd, offset, nbytes, flags);
343	}

arch/powerpc/kernel/sys_ppc32.c+9−0

@@ -810,3 +810,12 @@ asmlinkage long compat_sys_request_key(const char __user *_type, · 809 unmodified lines
810	return sys_request_key(_type, _description, _callout_info, destringid);	810	return sys_request_key(_type, _description, _callout_info, destringid);
811	}	811	}
812		812
		813	asmlinkage long compat_sys_sync_file_range2(int fd, unsigned int flags,
		814	unsigned offset_hi, unsigned offset_lo,
		815	unsigned nbytes_hi, unsigned nbytes_lo)
		816	{
		817	loff_t offset = ((loff_t)offset_hi << 32) \| offset_lo;
		818	loff_t nbytes = ((loff_t)nbytes_hi << 32) \| nbytes_lo;
		819
		820	return sys_sync_file_range(fd, offset, nbytes, flags);
		821	}

fs/sync.c+8−0

@@ -236,6 +236,14 @@ out: · 235 unmodified lines
236	return ret;	236	return ret;
237	}	237	}
238		238
		239	/* It would be nice if people remember that not all the world's an i386
		240	when they introduce new system calls */
		241	asmlinkage long sys_sync_file_range2(int fd, unsigned int flags,
		242	loff_t offset, loff_t nbytes)
		243	{
		244	return sys_sync_file_range(fd, offset, nbytes, flags);
		245	}
		246
239	/*	247	/*
240	* `endbyte' is inclusive	248	* `endbyte' is inclusive
241	*/	249	*/

include/asm-arm/unistd.h+1−0

@@ -367,6 +367,7 @@ · 366 unmodified lines
367	#define __NR_get_robust_list (__NR_SYSCALL_BASE+339)	367	#define __NR_get_robust_list (__NR_SYSCALL_BASE+339)
368	#define __NR_splice (__NR_SYSCALL_BASE+340)	368	#define __NR_splice (__NR_SYSCALL_BASE+340)
369	#define __NR_arm_sync_file_range (__NR_SYSCALL_BASE+341)	369	#define __NR_arm_sync_file_range (__NR_SYSCALL_BASE+341)
		370	#define __NR_sync_file_range2 __NR_arm_sync_file_range
370	#define __NR_tee (__NR_SYSCALL_BASE+342)	371	#define __NR_tee (__NR_SYSCALL_BASE+342)
371	#define __NR_vmsplice (__NR_SYSCALL_BASE+343)	372	#define __NR_vmsplice (__NR_SYSCALL_BASE+343)
372	#define __NR_move_pages (__NR_SYSCALL_BASE+344)	373	#define __NR_move_pages (__NR_SYSCALL_BASE+344)

include/asm-powerpc/systbl.h+1−0

@@ -311,3 +311,4 @@ COMPAT_SYS_SPU(utimensat) · 310 unmodified lines
311	COMPAT_SYS_SPU(signalfd)	311	COMPAT_SYS_SPU(signalfd)
312	COMPAT_SYS_SPU(timerfd)	312	COMPAT_SYS_SPU(timerfd)
313	SYSCALL_SPU(eventfd)	313	SYSCALL_SPU(eventfd)
		314	COMPAT_SYS_SPU(sync_file_range2)

include/asm-powerpc/unistd.h+2−1

 #define __NR_signalfd		305
 #define __NR_timerfd		306
 #define __NR_eventfd		307
+#define __NR_sync_file_range2	308
 #ifdef __KERNEL__
-#define __NR_syscalls		308
+#define __NR_syscalls		309
 #define __NR__exit __NR_exit
 #define NR_syscalls	__NR_syscalls

include/linux/syscalls.h+2−0

@@ -598,6 +598,8 @@ asmlinkage long sys_tee(int fdin, int fdout, size_t len, unsigned int flags); · 597 unmodified lines
598		598
599	asmlinkage long sys_sync_file_range(int fd, loff_t offset, loff_t nbytes,	599	asmlinkage long sys_sync_file_range(int fd, loff_t offset, loff_t nbytes,
600	unsigned int flags);	600	unsigned int flags);
		601	asmlinkage long sys_sync_file_range2(int fd, unsigned int flags,
		602	loff_t offset, loff_t nbytes);
601	asmlinkage long sys_get_robust_list(int pid,	603	asmlinkage long sys_get_robust_list(int pid,
602	struct robust_list_head __user * __user *head_ptr,	604	struct robust_list_head __user * __user *head_ptr,
603	size_t __user *len_ptr);	605	size_t __user *len_ptr);

scripts/checksyscalls.sh+5−0

 #define __IGNORE_setfsuid32
 #define __IGNORE_setfsgid32
+/* sync_file_range had a stupid ABI. Allow sync_file_range2 instead */
+#ifdef __NR_sync_file_range2
+#define __IGNORE_sync_file_range
+#endif
 /* Unmerged syscalls for AFS, STREAMS, etc. */
 #define __IGNORE_afs_syscall
 #define __IGNORE_getpmsg