On Thu, Jun 08, 2017 at 04:09:50PM +0100, Catalin Marinas wrote: > On Sun, Jun 04, 2017 at 02:59:51PM +0300, Yury Norov wrote: > > All new 32-bit architectures should have 64-bit off_t type, but existing > > architectures has 32-bit ones. > > > > To handle it, new config option is added to arch/Kconfig that defaults > > ARCH_32BIT_OFF_T to be disabled for non-64 bit architectures. All existing > > 32-bit architectures enable it explicitly here. > > > > New option affects force_o_largefile() behaviour. Namely, if off_t is > > 64-bits long, we have no reason to reject user to open big files. > > > > Note that even if architectures has only 64-bit off_t in the kernel > > (arc, c6x, h8300, hexagon, metag, nios2, openrisc, tile32 and unicore32), > > a libc may use 32-bit off_t, and therefore want to limit the file size > > to 4GB unless specified differently in the open flags. > > > > Signed-off-by: Yury Norov <ynorov@xxxxxxxxxxxxxxxxxx> > > Acked-by: Arnd Bergmann <arnd@xxxxxxxx> > [...] > > diff --git a/include/linux/fcntl.h b/include/linux/fcntl.h > > index 1b48d9c9a561..297993c92490 100644 > > --- a/include/linux/fcntl.h > > +++ b/include/linux/fcntl.h > > @@ -11,7 +11,7 @@ > > O_NOATIME | O_CLOEXEC | O_PATH | __O_TMPFILE) > > > > #ifndef force_o_largefile > > -#define force_o_largefile() (BITS_PER_LONG != 32) > > +#define force_o_largefile() (!IS_ENABLED(CONFIG_ARCH_32BIT_OFF_T)) > > #endif > > I may have confused myself with which off_t is 64-bit here for new > 32-bit architectures. Are we referring to the glibc definition, the > kernel one or simply that force_o_largefile() is true by default. > Because the type off_t for 32-bit kernel builds is still, well, 32-bit. > > Otherwise it seems that the first paragraph in the description above > should read "all new 32-bit ABIs on a 64-bit kernel..." but then > AArch64/ILP32 is no longer the same as a new, pure 32-bit architecture. This is all about userspace off_t types, like Arnd told in the comment to patch 13. I'll underline it in the comment to the patch. If it's not enough, I can also rename the config option to CONFIG_ARCH_32BIT_USER_OFF_T or similar. For me it's too much, but if you find it reasonable, I'll do it. Just let me know. Yury -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
