Hi,
On 2016/5/12 17:21, Arnd Bergmann wrote:
On Thursday 12 May 2016 10:17:58 Catalin Marinas wrote:
On Wed, May 11, 2016 at 09:30:07PM +0200, Arnd Bergmann wrote:
On Wednesday 11 May 2016 17:59:01 Catalin Marinas wrote:
I don't think the shifts are a problem, the main downside would be
the limit to 44 bits of file offsets (16TB files), but it's also
unclear if that is a practical problem at all. If it is, we run
into the same problem on all other 32-bit architectures too.
I hope people are seriously thinking of moving to an LP64 ABI if they
have such large file offset needs.
Good point. 44 bits of file size is certainly enough for mmap()
on a 32-bit task: you would only be able to map a very small fraction
of the file anyway, and if you want to map larger files, and should
move to 64-bit tasks long before this becomes a limitation.
Hi,
I apply the following patch in order to make use of the REAL mmmap2. LTP
test pass in litle endian. mmap16 successful with segfault in big endian.
BTW, I saw the similar code in tile, mips, microblaze and s390 compat. Should
we merge these code into a common syscall wrapper?
kernel:
diff --git a/arch/arm64/kernel/sys_ilp32.c b/arch/arm64/kernel/sys_ilp32.c
index d85fe94..2cd72eb 100644
--- a/arch/arm64/kernel/sys_ilp32.c
+++ b/arch/arm64/kernel/sys_ilp32.c
@@ -41,7 +41,16 @@
#define compat_sys_sync_file_range sys_sync_file_range
#define compat_sys_truncate64 sys_truncate
#define sys_llseek sys_lseek
-#define sys_mmap2 sys_mmap
+
+SYSCALL_DEFINE6(mmap2, unsigned long, addr, unsigned long, len,
+ unsigned long, prot, unsigned long, flags, unsigned long, fd,
+ unsigned long, pgoff)
+{
+ if (pgoff & (~PAGE_MASK >> 12))
+ return -EINVAL;
+
+ return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT-12));
+}
asmlinkage long ilp32_sys_rt_sigreturn_wrapper(void);
#define compat_sys_rt_sigreturn ilp32_sys_rt_sigreturn_wrapper
glibc:
diff --git a/sysdeps/unix/sysv/linux/aarch64/ilp32/mmap.c b/sysdeps/unix/sysv/linux/aarch64/ilp32/mmap.c
index e69de29..f75e251 100644
--- a/sysdeps/unix/sysv/linux/aarch64/ilp32/mmap.c
+++ b/sysdeps/unix/sysv/linux/aarch64/ilp32/mmap.c
@@ -0,0 +1,2 @@
+#include <sysdeps/unix/sysv/linux/generic/wordsize-32/mmap.c>
+
diff --git a/sysdeps/unix/sysv/linux/aarch64/ilp32/mmap64.c b/sysdeps/unix/sysv/linux/aarch64/ilp32/mmap64.c
index c6c7f1d..6f1a141 100644
--- a/sysdeps/unix/sysv/linux/aarch64/ilp32/mmap64.c
+++ b/sysdeps/unix/sysv/linux/aarch64/ilp32/mmap64.c
@@ -1,29 +1 @@
-#include <errno.h>
-#include <unistd.h>
-#include <sys/mman.h>
-#include <string.h>
-
-#include <sysdep.h>
-#include <sys/syscall.h>
-
-/* mmap is provided by mmap as they are the same. */
-void *__mmap (void *__addr, size_t __len, int __prot,
- int __flags, int __fd, __off_t __offset)
-{
- void *result;
- result = (void *) INLINE_SYSCALL (mmap2, 6, __addr, __len, __prot, __flags,
- return result;
-}
-/* mmap64 is provided by mmap as they are the same. */
-void *__mmap64 (void *__addr, size_t __len, int __prot,
- int __flags, int __fd, __off64_t __offset)
-{
- void *result;
- result = (void *)
- INLINE_SYSCALL (mmap2, 6, __addr,
- __len, __prot, __flags, __fd, __offset);
- return result;
-}
-weak_alias (__mmap, mmap)
-weak_alias (__mmap64, mmap64)
+#include <sysdeps/unix/sysv/linux/mmap64.c>
Regards
Bamvor
Arnd
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