From: Martin Schwidefsky This patch implements support of fallocate system call on s390(x) platform. A wrapper is added to address the issue which s390 ABI has with the arguments of this system call. Signed-off-by: Martin Schwidefsky --- arch/s390/kernel/compat_wrapper.S | 10 ++++++++++ arch/s390/kernel/sys_s390.c | 20 ++++++++++++++++++++ arch/s390/kernel/syscalls.S | 2 +- include/asm-s390/unistd.h | 2 +- 4 files changed, 32 insertions(+), 2 deletions(-) Index: quilt-2.6/arch/s390/kernel/compat_wrapper.S =================================================================== --- quilt-2.6.orig/arch/s390/kernel/compat_wrapper.S +++ quilt-2.6/arch/s390/kernel/compat_wrapper.S @@ -1710,3 +1710,13 @@ compat_sys_timerfd_wrapper: sys_eventfd_wrapper: llgfr %r2,%r2 # unsigned int jg sys_eventfd + + .globl sys_fallocate_wrapper +sys_fallocate_wrapper: + lgfr %r2,%r2 # int + lgfr %r3,%r3 # int + sllg %r4,%r4,32 # get high word of 64bit loff_t + lr %r4,%r5 # get low word of 64bit loff_t + sllg %r5,%r6,32 # get high word of 64bit loff_t + l %r5,164(%r15) # get low word of 64bit loff_t + jg sys_fallocate Index: quilt-2.6/arch/s390/kernel/syscalls.S =================================================================== --- quilt-2.6.orig/arch/s390/kernel/syscalls.S +++ quilt-2.6/arch/s390/kernel/syscalls.S @@ -322,7 +322,7 @@ NI_SYSCALL /* 310 sys_move_pages * SYSCALL(sys_getcpu,sys_getcpu,sys_getcpu_wrapper) SYSCALL(sys_epoll_pwait,sys_epoll_pwait,compat_sys_epoll_pwait_wrapper) SYSCALL(sys_utimes,sys_utimes,compat_sys_utimes_wrapper) -NI_SYSCALL /* 314 sys_fallocate */ +SYSCALL(s390_fallocate,sys_fallocate,sys_fallocate_wrapper) SYSCALL(sys_utimensat,sys_utimensat,compat_sys_utimensat_wrapper) /* 315 */ SYSCALL(sys_signalfd,sys_signalfd,compat_sys_signalfd_wrapper) SYSCALL(sys_timerfd,sys_timerfd,compat_sys_timerfd_wrapper) Index: quilt-2.6/arch/s390/kernel/sys_s390.c =================================================================== --- quilt-2.6.orig/arch/s390/kernel/sys_s390.c +++ quilt-2.6/arch/s390/kernel/sys_s390.c @@ -265,3 +265,23 @@ s390_fadvise64_64(struct fadvise64_64_ar return -EFAULT; return sys_fadvise64_64(a.fd, a.offset, a.len, a.advice); } + +#ifndef CONFIG_64BIT +/* + * This is a wrapper to call sys_fallocate(). For 31 bit s390 the last + * 64 bit argument "len" is split into the upper and lower 32 bits. The + * system call wrapper in the user space loads the value to %r6/%r7. + * The code in entry.S keeps the values in %r2 - %r6 where they are and + * stores %r7 to 96(%r15). But the standard C linkage requires that + * the whole 64 bit value for len is stored on the stack and doesn't + * use %r6 at all. So s390_fallocate has to convert the arguments from + * %r2: fd, %r3: mode, %r4/%r5: offset, %r6/96(%r15)-99(%r15): len + * to + * %r2: fd, %r3: mode, %r4/%r5: offset, 96(%r15)-103(%r15): len + */ +asmlinkage long s390_fallocate(int fd, int mode, loff_t offset, + u32 len_high, u32 len_low) +{ + return sys_fallocate(fd, mode, offset, ((u64)len_high << 32) | len_low); +} +#endif Index: quilt-2.6/include/asm-s390/unistd.h =================================================================== --- quilt-2.6.orig/include/asm-s390/unistd.h +++ quilt-2.6/include/asm-s390/unistd.h @@ -251,7 +251,7 @@ #define __NR_getcpu 311 #define __NR_epoll_pwait 312 #define __NR_utimes 313 -/* Number 314 is reserved for new sys_fallocate */ +#define __NR_fallocate 314 #define __NR_utimensat 315 #define __NR_signalfd 316 #define __NR_timerfd 317 -- blue skies, Martin. "Reality continues to ruin my life." - Calvin. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/